1. 变量 ❎
变量是用于存储值（字符串、整数、浮点数、布尔值）的容器。
变量的行为就像它包含的值一样。
# 字符串
first_name = "Bro"
food = "pizza"
email = "Bro123@gmail.com"
print(f"你好 {first_name}")
print(f"你喜欢 {food}")
print(f"你的邮箱是: {email}")
# 整数
age = 25
quantity = 3
num_of_students =30
print(f"你 {age} 岁了")
print(f"你购买了 {quantity} 件商品")
print(f"你的班级有 {num_of_students} 名学生")
# 浮点数
price = 10.99
gpa = 3.2
distance = 5.5
print(f"价格是 ${price}")
print(f"你的 GPA 是: {gpa}")
print(f"你跑了 {distance} 公里")
# 布尔值
is_student = False
for_sale = False
is_online = True
if is_online:
print("你在线")
else:
print("你离线")
变量赋值
user_name = "Yuuniji"
year = 2025
pi = 3.14
is_admin = True
print(f"用户名: {user_name}")
print(f"当前年份: {year}")
# 四舍五入到两位小数
print(f"Pi: {pi:.2f}")
# 将布尔值转换为 '是' 或 '否'
print(f"管理员状态: {'是' if is_admin else '否'}")
2. 类型转换 💱
类型转换是将变量从一种数据类型转换为另一种数据类型的过程。
str(), int(), float(), bool()
name = "Yuuniji"
age = 25
gpa = 3.2
is_student = True
# print(type(name))
gpa = int(gpa) # 3
age = float(age) # 25.0
age = str(age)
age += "1" # "251"
name = bool(name) # True
3. 用户输入 ⌨️
一个提示用户输入数据的函数。
返回输入的数据作为字符串。
name = input("你叫什么名字？: ")
age = int(input("你多大了？: "))
# age = int(age)
age = age + 1
print(f"你好 {name}!")
print("生日快乐")
print(f"你 {age} 岁了")
练习 1 矩形面积计算
length = float(intput("输入长度: "))
width = float(intput("输入宽度: "))
area = length * width
print(f"面积是: {area}cm²")
#Mac 上标 2: Command + Control + Space, 在搜索栏中输入“superscript”或“2”。或者 Option + v
练习 2 购物车程序
item = input("你想买什么商品？: ")
price = float(input("价格是多少？: "))
quantity = int(input("你想买多少？: "))
total = price * quantity
print(f"你购买了 {quantity} 件 {item}")
print(f"总价是: ${total}")
4. ⭐ 填词游戏
填词游戏是一种通过用随机单词填空来创建故事的文字游戏。
adjective1 = input("输入一个形容词（描述）: ")
noun1 = input("输入一个名词（人、地点、事物）: ")
adjective2 = input("输入一个形容词（描述）: ")
verb1 = input("输入一个以 'ing' 结尾的动词")
adjective3 = input("输入一个形容词（描述）: ")
print(f"今天我去了一家 {adjective1} 动物园。")
print(f"在一个展区，我看到了一只 {noun1}")
print(f"{noun1} 是 {adjective2} 并且 {verb1}")
print(f"我感到 {adjective3}!")
5. 算术运算符和数学函数 📐
friends = 10
friends = friends + 1
friends += 1
friends = friends - 2
friends -= 2
friends = friends * 3
friends *= 3
friends = friends / 2
friends /= 2
friends = friends ** 2
friends **= 2
remainder = friends % 3
x = 3.14
y = 4
z = 5
result = round(x) # 3
result = abs(y) # 4
result = pow(4, 3) # 4*4*4=64
result = max(x, y, z) # 5
result = min(x, y, z) # 3.14
import math
x = 9
y = 9.1
z = 9.9
print(math.pi) # 3.141592653589793
print(math.e) # 2.718281828459045
result = math.sqrt(x) # 3.0
result = math.ceil(y) # 10
result = math.floor(z) # 9
# C = 2πr
import math
radius = float(input('输入圆的半径: ')) # 10.5
circumference = 2 * math.pi *radius
print(f"周长是: {round(circumference, 2)}cm") # 65.97
# A = πr²
import math
radius = float(input('输入圆的半径: ')) # 10.5
area = math.pi * pow(radius, 2)
print(f"圆的面积是: {round(area, 2)}cm²") # 346.36
# c = √(a²+b²)
import math
a = float(input("输入边 A: ")) # 3
b = float(input("输入边 B: ")) # 4
c = math.sqrt(pow(a, 2) + pow(b, 2))
print(f"边 C = {c}") # 5.0
6. if 语句 🤔
仅在某个条件为真时执行某些代码
否则执行其他操作
age = int(input("请输入您的年龄: "))
if age >= 100:
print("您年龄太大，无法注册")
elif age >= 18:
print("您已成功注册！")
elif age < 0:
print("您还未出生！")
else:
print("您必须年满18岁才能注册")
response = input("您想要食物吗？(Y/N): ")
if response == "Y":
print("请享用食物！")
else:
print("没有食物给您！")
name = input("请输入您的名字: ")
if name == "":
print("您没有输入名字！")
else:
print(f"您好 {name}")
for_sale = True
if for_sale:
print("此商品正在出售")
else:
print("此商品不在出售")
7. ⭐ 计算器程序 🧮
# + = 加法
# - = 减法
# * = 乘法
# / = 除法
operator = input("请输入运算符 (+ - * /): ")
num1 = float(input("请输入第一个数字: "))
num2 = float(input("请输入第二个数字: "))
if operator == "+":
result = num1 + num2
print(round(result, 3))
elif operator == "-":
result = num1 - num2
print(round(result, 3))
elif operator == "*":
result = num1 * num2
print(round(result, 3))
elif operator == "/":
result = num1 / num2
print(round(result, 3))
else:
print(f"{operator} 不是一个有效的运算符")
8. ⭐ 重量转换程序 🏋️
weight = float(input("请输入您的体重: "))
unit = input("千克还是磅？(K 或 L): ")
if unit == "K":
weight = weight * 2.205
unit = "磅"
print(f"您的体重是: {round(weight, 1)} {unit}")
elif unit == "L":
weight = weight / 2.205
unit = "千克"
print(f"您的体重是: {round(weight, 1)} {unit}")
else:
print(f"{unit} 不是一个有效的单位")
9. ⭐ 温度转换程序 🌡️
# (°C x 9/5) + 32 = °F
# (°F - 32) x 5/9 = °C
# °(Option + Shift + 8)
unit = input("温度单位是摄氏度还是华氏度？(C/F): ")
temp = float(input("请输入温度: "))
if unit == "C":
temp = round((9 * temp) / 5 + 32, 1)
print(f"华氏温度为: {temp}°F")
elif unit == "F":
temp = round((temp - 32) * 5 / 9, 1)
print(f"摄氏温度为: {temp}°C")
else:
print(f"{unit} 不是一个有效的温度单位")
10. 逻辑运算符 🌦️
用于评估多个条件（或、且、非）
or = 至少一个条件必须为真
and = 两个条件都必须为真
not = 反转条件（非假，非真）
temp = 25
is_raining = True
if temp > 35 or temp < 0 or is_raining:
print("户外活动已取消")
else:
print("户外活动仍按计划进行")
temp = 25
is_sunny = True
if temp >= 28 and is_sunny:
print("外面很热 🥵")
print("天气晴朗 🌞")
elif temp <= 0 and is_sunny:
print("外面很冷 🥶")
print("天气晴朗 🌞")
elif 28 > temp > 0 and is_sunny:
print("外面很温暖 🙂")
print("天气晴朗 🌞")
elif temp >= 28 and not is_sunny:
print("外面很热 🥵")
print("天气多云 ☁️")
elif temp <= 0 and not is_sunny:
print("外面很冷 🥶")
print("天气多云 ☁️")
elif 28 > temp > 0 and not is_sunny:
print("外面很温暖 🙂")
print("天气多云 ☁️")
11. 条件表达式 ❓
if-else 语句的一行快捷方式（三元运算符）
根据条件打印或分配两个值之一
X if condition else Y
num = 5
a = 6
b = 7
age = 13
temperature = 20
user_role = "guest"
print("正数" if num > 0 else "负数")
result = "偶数" if num % 2 == 0 else "奇数"
max_num = a if a > b else b
min_num = a if a < b else b
status = "成年人" if age >= 18 else "儿童"
weather = "热" if temperature > 20 else "冷"
access_level = "完全访问" if user_role == "admin" else "受限访问"
print(access_level)
12. 字符串方法 〰️
name = input("请输入您的全名：")
result = len(name)
# yuunijiy -> 8
result = name.find("n")
# yuunijiy -> 3
result = name.rfind("n")
# yuunijiy -> 4
name = name.capitalize()
# yuunijiy -> Yuunijiy
name = name.upper()
# yuunijiy -> YUUNIJIY
name = name.lower()
# YUUNIJIY -> yuunijiy
result = name.isdigit()
# yuunijiy,yuu123 -> False; 123 -> True
result = name.isalpha()
# yuunijiy -> True; yuu niji,yuu123,123 -> False
phone_number = input("请输入您的电话号码：")
result = phone_number.count("-")
# 1-234-567-8901 -> 3
phone_number = phone_number.replace("-", " ")
# 1-234-567-8901 -> 1 234 567 8901
如果你想查看所有可用的字符串方法的完整列表，可以使用帮助函数：print(help(str))
练习：
# 验证用户输入练习
# 1. 用户名不能超过12个字符
# 2. 用户名不能包含空格
# 3. 用户名不能包含数字
username = input("请输入用户名：")
if len(username) > 12:
print("您的用户名不能超过12个字符")
elif not username.find(" ") == -1:
print("您的用户名不能包含空格")
elif not username.isalpha():
print("您的用户名不能包含数字")
else:
print(f"欢迎 {username}")
13. 字符串索引 ✂️
使用 [] 访问序列中的元素（索引操作符）
[起始 : 结束 : 步长]
credit_number = "1234-5678-9012-3456"
print(credit_number[0]) # 1
print(credit_number[:4]) # 1234
print(credit_number[5:9]) # 5678
print(credit_number[5:]) # 5678-9012-3456
print(credit_number[-1]) # 6
print(credit_number[-2]) # 5
print(credit_number[::2]) # 13-6891-46
print(credit_number[::3]) # 146-136
credit_number = "1234-5678-9012-3456"
last_digits = credit_number[-4:] # 3456
print(f"XXXX-XXXX-XXXX-{last_digits}")
credit_number = "1234-5678-9012-3456"
credit_number = credit_number[::-1]
print(credit_number)
# 6543-2109-8765-4321
14. 格式说明符 💬
{value:flags} 根据插入的标志格式化值
.(数字)f= 四舍五入到指定的小数位数（定点数）:(数字)= 分配指定数量的空格:03= 分配并用零填充指定数量的空格:<= 左对齐:>= 右对齐:^= 居中对齐:+= 使用加号表示正值:== 将符号放在最左侧位置:= 在正数前插入空格:,= 逗号分隔符
price1 = 3.14159
price2 = -987.65
price3 = 12.34
print(f"价格 1 是 ${price1:.3f}") # 3.142
print(f"价格 2 是 ${price2:.3f}") # -987.650
print(f"价格 3 是 ${price3:.3f}") # 12.340
print(f"价格 1 是 ${price1:10}")
print(f"价格 2 是 ${price2:10}")
print(f"价格 3 是 ${price3:10}")
# 价格 1 是 $ 3.14159
# 价格 2 是 $ -987.65
# 价格 3 是 $ 12.34
print(f"价格 1 是 ${price1:010}")
print(f"价格 2 是 ${price2:010}")
print(f"价格 3 是 ${price3:010}")
# 价格 1 是 $0003.14159
# 价格 2 是 $-000987.65
# 价格 3 是 $0000012.34
print(f"价格 1 是 ${price1:<10}")
print(f"价格 2 是 ${price2:<10}")
print(f"价格 3 是 ${price3:<10}")
# 价格 1 是 $3.14159 |
# 价格 2 是 $-987.65 |
# 价格 3 是 $12.34 |
print(f"价格 1 是 ${price1:+}") # +3.14159
print(f"价格 2 是 ${price2:+}") # -987.65
print(f"价格 3 是 ${price3:+}") # +12.34
print(f"价格 1 是 ${price1:10}")
print(f"价格 2 是 ${price2:10}")
print(f"价格 3 是 ${price3:10}")
# 价格 1 是 $ 3.14159
# 价格 2 是 $-987.65
# 价格 3 是 $ 12.34
price1 = 3000.14159
price2 = -9870.65
price3 = 1200.34
print(f"价格 1 是 ${price1:,}")
print(f"价格 2 是 ${price2:,}")
print(f"价格 3 是 ${price3:,}")
# 价格 1 是 $3,000.14159
# 价格 2 是 $-9,870.65
# 价格 3 是 $1,200.34
print(f"价格 1 是 ${price1:+,.2f}")
print(f"价格 2 是 ${price2:+,.2f}")
print(f"价格 3 是 ${price3:+,.2f}")
# 价格 1 是 $+3,000.14
# 价格 2 是 $-9,870.65
# 价格 3 是 $+1,200.34
15. while 循环 ♾️
当某个条件为真时执行一些代码
age = int(input("请输入您的年龄: "))
while age < 0:
print("年龄不能为负数")
age = int(input("请输入您的年龄: "))
print(f"您 {age} 岁了")
food = input("输入您喜欢的食物 (q 退出): ")
while not food == "q":
print(f"您喜欢 {food}")
food = input("输入您喜欢的另一种食物 (q 退出): ")
print("再见")
num = int(input("输入一个 1 - 10 之间的数字: "))
while num < 1 or num > 10:
print(f"{num} 无效")
num = int(input("输入一个 1 - 10 之间的数字: "))
print(f"您的数字是 {num}")
16. ⭐ 复利计算器 💵
# A = P (1 + r/n)ᵗ
# A = 最终金额
# P = 初始本金
# r = 利率
# t = 经过的时间段数
principle = 0
rate = 0
time = 0
while principle <= 0:
principle = float(input("输入本金金额: "))
if principle <= 0:
print("本金不能小于或等于零")
while rate <= 0:
rate = float(input("输入利率: "))
if rate <= 0:
print("利率不能小于或等于零")
while time <= 0:
time = int(input("输入时间（年）: "))
if time <= 0:
print("时间不能小于或等于零")
print(principle)
print(rate)
print(time)
total = principle * pow((1 + rate / 100), time)
print(f"{time} 年后的余额: ${total:.2f}")
principle = 0
rate = 0
time = 0
while True:
principle = float(input("输入本金金额: "))
if principle < 0:
print("本金不能小于零")
else:
break
while True:
rate = float(input("输入利率: "))
if rate < 0:
print("利率不能小于零")
else:
break
while True:
time = int(input("输入时间（年）: "))
if time < 0:
print("时间不能小于零")
else:
break
total = principle * pow((1 + rate / 100), time)
print(f"{time} 年后的余额: ${total:.2f}")
17. for 循环 🔁
重复执行一段代码固定的次数。
你可以遍历一个范围、字符串、序列等。
for x in range(1, 6):
print(x)
# 1
# 2
# 3
# 4
# 5
for x in reversed(range(1, 6)):
print(x)
print("HAPPY NEW YEAR!")
# 1
# 2
# 3
# 4
# 5
# HAPPY NEW YEAR!
for x in range(1, 6, 3):
print(x)
# 1
# 4
credit_card = "12-34"
for x in credit_card:
print(x)
# 1
# 2
# -
# 3
# 4
for x in range(1, 6):
if x == 3:
continue
else:
print(x)
# 1
# 2
# 4
# 5
for x in range(1, 6):
if x == 3:
break
else:
print(x)
# 1
# 2
18. ⭐ 倒计时程序 ⌛
import time
my_time = int(input("请输入时间（秒）：")) # 3
for x in range(0, my_time):
print(x)
time.sleep(1)
# 0
# 1
# 2
print("时间到！")
import time
my_time = int(input("请输入时间（秒）：")) # 3
for x in range(my_time, 0, -1):
print(x)
time.sleep(1)
# 3
# 2
# 1
print("时间到！")
import time
my_time = int(input("请输入时间（秒）：")) # 3605
for x in range(my_time, 0, -1):
seconds = x % 60
minutes = int(x / 60) % 60
hours = int(x / 3600)
print(f"{hours:02}:{minutes:02}:{seconds:02}")
time.sleep(1)
# 01:00:05
# 01:00:04
# 01:00:03
# 01:00:02
# 01:00:01
# 01:00:00
# 00:59:59
# 00:59:58
print("时间到！")
19. 嵌套循环 ➿
一个循环嵌套在另一个循环中（外层循环，内层循环）
外层循环:
内层循环:
for x in range(1, 10):
print(x, end="")
# 123456789
for x in range(3):
for y in range(1, 10):
print(y, end="")
# 123456789123456789123456789
for x in range(3):
for y in range(1, 10):
print(y, end="")
print()
# 123456789
# 123456789
# 123456789
rows = int(input("请输入行数：")) # 3
columns = int(input("请输入列数：")) # 5
symbol = input("请输入要使用的符号：") # *
for x in range(rows):
for y in range(columns):
print(symbol, end="")
print()
# *****
# *****
# *****
20. 列表、集合和元组 🍎
- 集合 = 用于存储多个值的单一“变量”
- 列表 =
[]有序且可更改。允许重复 - 集合 =
{}无序且不可变，但可以添加/删除元素。不允许重复 - 元组 =
()有序且不可更改。允许重复。速度更快
fruits = ["苹果", "橙子", "香蕉", "椰子"]
# print(help(fruits))
print(dir(fruits))
# ['__add__', '__class__', '__contains__', '__delattr__', '__delitem__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__getitem__', '__gt__', '__hash__', '__iadd__', '__imul__', '__init__', '__init_subclass__', '__iter__', '__le__', '__len__', '__lt__', '__mul__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__reversed__', '__rmul__', '__setattr__', '__setitem__', '__sizeof__', '__str__', '__subclasshook__', 'append', 'clear', 'copy', 'count', 'extend', 'index', 'insert', 'pop', 'remove', 'reverse', 'sort']
print("苹果" in fruits) # True
print(fruits[0]) # 苹果
print(fruits[0:3])
# ["苹果", "橙子", "香蕉"]
print(fruits[::2])
# ["苹果", "香蕉"]
print(fruits[::-1])
# ["椰子", "香蕉", "橙子", "苹果"]
fruits = ["苹果", "橙子", "香蕉", "椰子"]
fruits.append("菠萝")
# fruits.remove("菠萝")
print(fruits)
# ["苹果", "橙子", "香蕉", "椰子", "菠萝"]
fruits = ["苹果", "橙子", "香蕉", "椰子"]
fruits.insert(0, "菠萝")
print(fruits)
# ["菠萝", "苹果", "橙子", "香蕉", "椰子"]
fruits = ["苹果", "橙子", "香蕉", "椰子"]
fruits.sort()
print(fruits)
# ["苹果", "香蕉", "椰子", "橙子"]
fruits = ["苹果", "橙子", "香蕉", "椰子"]
fruits.reverse()
print(fruits)
# ["椰子", "香蕉", "橙子", "苹果"]
fruits = ["苹果", "橙子", "香蕉", "椰子"]
fruits.sort()
fruits.reverse()
print(fruits)
# ["橙子", "椰子", "香蕉", "苹果"]
fruits = ["苹果", "橙子", "香蕉", "椰子"]
fruits.clear()
print(fruits)
# []
fruits = ["苹果", "橙子", "香蕉", "椰子"]
print(fruits.index("苹果")) # 0
fruits = {"苹果", "橙子", "香蕉", "椰子", "椰子"}
print(len(fruits)) # 4
print(dir(fruits))
# ['__and__', '__class__', '__contains__', '__delattr__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__gt__', '__hash__', '__iand__', '__init__', '__init_subclass__', '__iter__', '__ixor__', '__le__', '__len__', '__lt__', '__ne__', '__new__', '__or__', '__rand__', '__reduce__', '__reduce_ex__', '__repr__', '__ror__', '__rxor__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '__xor__', 'add', 'clear', 'copy', 'difference', 'difference_update', 'discard', 'intersection', 'intersection_update', 'isdisjoint', 'issubset', 'issuperset', 'pop', 'remove', 'symmetric_difference', 'symmetric_difference_update', 'union', 'update']
print(fruits[0])
# TypeError: 'set' object is not subscriptable
print(fruits)
# {"橙子", "苹果", "香蕉", "椰子"}
fruits.pop()
# {"橙子", "苹果", "香蕉"}
# OR {"苹果", "香蕉", "椰子"}
# OR {"橙子", "香蕉", "椰子"}
# OR ...
fruits.clear() # set()
fruits = ("苹果", "橙子", "香蕉", "椰子", "椰子")
print(dir(fruits))
# ['__add__', '__class__', '__contains__', '__delattr__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__getitem__', '__getnewargs__', '__gt__', '__hash__', '__init__', '__init_subclass__', '__iter__', '__le__', '__len__', '__lt__', '__mul__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__rmul__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', 'count', 'index']
print(fruits)
# ("苹果", "橙子", "香蕉", "椰子", "椰子")
21. ⭐ 购物车程序 🛒
foods = []
prices = []
total = 0
while True:
food = input("请输入要购买的食物（输入q退出）：")
if food.lower() == "q":
break
else:
price = float(input(f"请输入{food}的价格：$"))
foods.append(food)
prices.append(price)
print("----- 您的购物车 -----")
for food in foods:
print(food, end=" ")
for price in prices:
total += price
print()
print(f"您的总金额是：${total}")
22. 二维集合 ⬜
fruits = ["苹果", "橙子", "香蕉", "椰子"]
vegetables = ["芹菜", "胡萝卜", "土豆"]
meats = ["鸡肉", "鱼", "火鸡"]
groceries = [fruits, vegetables, meats]
print(groceries[0])
# ["苹果", "橙子", "香蕉", "椰子"]
print(groceries[0][3])
# 椰子
print(groceries[2][3])
# IndexError: 列表索引超出范围
groceries = [["苹果", "橙子", "香蕉", "椰子"],
["芹菜", "胡萝卜", "土豆"],
["鸡肉", "鱼", "火鸡"]]
for collection in groceries:
for food in collection:
print(food, end=" ")
print()
# 苹果 橙子 香蕉 椰子
# 芹菜 胡萝卜 土豆
# 鸡肉 鱼 火鸡
num_pad = ((1, 2, 3),
(4, 5, 6),
(7, 8, 9),
("*", 0, "#"))
for row in num_pad:
for num in row:
print(num, end=" ")
print()
# 1 2 3
# 4 5 6
# 7 8 9
# * 0 #
23. ⭐ 问答游戏 💯
questions = ("元素周期表中有多少个元素？：",
"哪种动物产的蛋最大？：",
"地球大气中含量最多的气体是什么？：",
"人体有多少块骨头？：",
"太阳系中最热的行星是哪个？：")
options = (("A. 116", "B. 117", "C. 118", "D. 119"),
("A. 鲸鱼", "B. 鳄鱼", "C. 大象", "D. 鸵鸟"),
("A. 氮气", "B. 氧气", "C. 二氧化碳", "D. 氢气"),
("A. 206", "B. 207", "C. 208", "D. 209"),
("A. 水星", "B. 金星", "C. 地球", "D. 火星"))
answers = ("C", "D", "A", "A", "B" )
guesses = []
score = 0
question_num = 0
for question in questions:
print("-----------------------")
print(question)
for option in options[question_num]:
print(option)
guess = input("输入（A, B, C, D）：").upper()
guesses.append(guess)
if guess == answers[question_num]:
score += 1
print("正确！")
else:
print("错误！")
print(f"正确答案是 {answers[question_num]}")
question_num += 1
print("-----------------------")
print(" 结果 ")
print("-----------------------")
print("答案：", end="")
for answer in answers:
print(answer, end=" ")
print()
print("猜测：", end="")
for guess in guesses:
print(guess, end=" ")
print()
score = int(score / len(questions) * 100)
print(f"您的得分是：{score}%")
24. 字典 📙
字典是一个有序且可变的{键:值}对集合。不允许重复。
capitals = {"USA": "Washington D.C.",
"India": "New Delhi",
"China": "Beijing",
"Russia": "Moscow"}
print(dir(capitals))
# print(help(capitals))
# ['__class__', '__contains__', '__delattr__', '__delitem__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__getitem__', '__gt__', '__hash__', '__init__', '__init_subclass__', '__iter__', '__le__', '__len__', '__lt__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__setitem__', '__sizeof__', '__str__', '__subclasshook__', 'clear', 'copy', 'fromkeys', 'get', 'items', 'keys', 'pop', 'popitem', 'setdefault', 'update', 'values']
print(capitals.get("USA")) # Washington D.C.
print(capitals.get("Japan")) # None
capitals.update({"Germany": "Berlin"})
capitals.update({"USA": "Detroit"})
# {"USA": "Detroit", "India": "New Delhi", "China": "Beijing", "Russia": "Moscow", "Germany": "Berlin"}
capitals.pop("China")
# {"USA": "Detroit", "India": "New Delhi", "Russia": "Moscow", "Germany": "Berlin"}
capitals.popitem()
# {"USA": "Detroit", "India": "New Delhi", "Russia": "Moscow"}
# capitals.clear()
# {}
keys = capitals.keys()
# dict_keys(['USA', 'India', 'Russia'])
for keys in capitals.keys():
print(key)
# USA
# India
# Russia
values = capitals.values()
# dict_values(['Detroit', 'New Delhi', 'Moscow'])
for value in capitals.values():
print(value)
# Detroit
# New Delhi
# Moscow
items = capitals.items()
print(items)
# dict_items([('USA', 'Detroit'), ('India', 'New Delhi'), ('Russia', 'Moscow')])
for key, value in capitals.items():
print(f"{key}: {value}")
# USA: Detroit
# India: New Delhi
# Russia: Moscow
25. ⭐ 小吃摊程序 🍿
menu = {"pizza": 3.00, # 披萨
"nachos": 4.50, # 玉米片
"popcorn": 6.00, # 爆米花
"fries": 2.50, # 薯条
"chips": 1.00, # 薯片
"pretzel": 3.50, # 椒盐卷饼
"soda": 3.00, # 汽水
"lemonade": 4.25} # 柠檬水
cart = []
total = 0
print("----- 菜单 -----")
for key, value in menu.items():
print(f"{key:10}: ${value:.2f}")
print("----------------")
while True:
food = input("选择一项商品（输入 q 退出）：").lower()
if food == "q":
break
elif menu.get(food) is not None:
cart.append(food)
print("-- 您的订单 --")
for food in cart:
total += menu.get(food)
print(food, end=" ")
print()
print(f"总金额为: ${total:.2f}")
26. 随机数 🎲
import random
# print(help random) # 查看 random 模块的帮助文档
low = 1
high = 100
options = ("rock", "paper", "scissors") # 石头、剪刀、布
cards = ["2", "3", "4", "5", "6", "7", "8", "9", "10", "J", "Q", "K", "A"] # 扑克牌
# number = random.randint(1, 6) # 生成 1 到 6 之间的整数
# number = random.randint(low, high) # 生成 low 到 high 之间的整数
# number = random.random() # 生成 0 到 1 之间的随机浮点数
# option = random.choice(options) # 随机选择一项
# random.shuffle(cards) # 洗牌
27. ⭐ 猜数字游戏 🔢
import random
lowest_num = 1
highest_num = 100
answer = random.randint(lowest_num, highest_num)
guesses = 0
is_running = True
print("Python 猜数字游戏")
print(f"请选择一个 {lowest_num} 到 {highest_num} 之间的数字")
while is_running:
guess = input("请输入你的猜测：")
if guess.isdigit():
guess = int(guess)
guesses += 1
if guess < lowest_num or guess > highest_num:
print("这个数字超出了范围")
print(f"请选择一个 {lowest_num} 到 {highest_num} 之间的数字")
elif guess < answer:
print("太小了！再试一次！")
elif guess > answer:
print("太大了！再试一次！")
else:
print(f"正确！答案就是 {answer}")
print(f"猜了 {guesses} 次")
is_running = False
else:
print("输入无效")
print(f"请选择一个 {lowest_num} 到 {highest_num} 之间的数字")
28. ⭐ 石头剪刀布游戏 🗿
import random
options = ("rock", "paper", "scissors")
playing = True
while playing:
player = None
computer = random.choice(options)
while player not in options:
player = input("请输入选择（石头、纸、剪刀）：")
print(f"玩家: {player}")
print(f"电脑: {computer}")
if player == computer:
print("平局！")
elif player == "rock" and computer == "scissors":
print("你赢了！")
elif player == "paper" and computer == "rock":
print("你赢了！")
elif player == "scissors" and computer == "paper":
print("你赢了！")
else:
print("你输了！")
play_again = input("再玩一局？（y/n）：").lower()
if not play_again == "y":
playing = False
print("感谢游玩！")
29. ⭐ 骰子滚动程序 ⚂
import random
print("\u25CF \u250C \u2500 \u2510 \u2502 \u2514 \u2518")
# ● ┌ ─ ┐ │ └ ┘
"┌─────────┐"
"│ │"
"│ │"
"│ │"
"└─────────┘"
dice_art = {
1: ("┌─────────┐",
"│ │",
"│ ● │",
"│ │",
"└─────────┘"),
2: ("┌─────────┐",
"│ ● │",
"│ │",
"│ ● │",
"└─────────┘"),
3: ("┌─────────┐",
"│ ● │",
"│ ● │",
"│ ● │",
"└─────────┘"),
4: ("┌─────────┐",
"│ ● ● │",
"│ │",
"│ ● ● │",
"└─────────┘"),
5: ("┌─────────┐",
"│ ● ● │",
"│ ● │",
"│ ● ● │",
"└─────────┘"),
6: ("┌─────────┐",
"│ ● ● │",
"│ ● ● │",
"│ ● ● │",
"└─────────┘"),
}
dice = []
total = 0
num_of_dice = int(input("请输入骰子数量："))
for die in range(num_of_dice):
dice.append(random.randint(1, 6))
print(dice)
# for die in range(num_of_dice):
# for line in dice_art.get(dice[die]):
# print(line)
for line in range(5): # 外部循环，按行打印
for die in dice: # 内部循环，遍历每个骰子的点数
print(dice_art.get(die)[line], end="") # 打印当前骰子图案的当前行
print() # 每打印完一行后换行
for die in dice:
total += die
print(f"总和: {total}")
30. 函数 📞
# 函数 = 一段可重用的代码块
# 在函数名后加 () 来调用它
def happy_birthday(name, age):
print(f"祝 {name} 生日快乐！")
print(f"你今年 {age} 岁！")
print("祝你生日快乐！")
print()
happy_birthday("Bro", 20)
happy_birthday("Steve", 30)
happy_birthday("Joe", 40)
--------
def display_invoice(username, amount, due_date):
print(f"你好 {username}")
print(f"你的账单金额 ${amount:.2f} 将于 {due_date} 到期")
display_invoice("YuuNiji", 100.01, "01/02")
--------
# return = 用于结束函数并将结果返回给调用者
def add(x, y):
z = x + y
return z
def subtract(x, y):
z = x - y
return z
def multiply(x, y):
z = x * y
return z
def divide(x, y):
z = x / y
return z
print(add(1, 2)) # 3
print(subtract(1, 2)) # -1
print(multiply(1, 2)) # 2
print(divide(1, 2)) # 0.5
--------
def create_name(first, last):
first = first.capitalize()
last = last.capitalize()
return first + " " + last
full_name = create_name("yuuniji", "code")
print(full_name) # Yuuniji Code
31. 默认参数 👍
# 默认参数 = 为某些参数设置默认值
# 当省略该参数时使用默认值
# 使函数更灵活，减少参数数量
# 1. 位置参数 2. 默认参数 3. 关键字参数 4. 任意参数
def net_price(list_price, discount=1, tax=0.05):
return list_price * (1 - discount) * (1 + tax)
print(net_price(500)) # 525.0
print(net_price(500, 0.1)) # 472.5
print(net_price(500, 0.1, 0)) # 450
--------
import time
def count(start, end):
for x in range(start, end+1):
print(x)
time.sleep(1)
print("完成！")
count(0, 10)
# 0
# 1
# 2
# 3
# 4
# 5
# 6
# 7
# 8
# 9
# 10
# 完成！
--------
import time
def count(start=0, end):
for x in range(start, end+1):
print(x)
time.sleep(1)
print("完成！")
count(10)
# SyntaxError: 非默认参数不能在默认参数之后
--------
import time
def count(end, start=0):
for x in range(start, end+1):
print(x)
time.sleep(1)
print("完成！")
count(10)
# 0
# 1
# 2
# 3
# 4
# 5
# 6
# 7
# 8
# 9
# 10
# 完成！
--------
import time
def count(end, start=0):
for x in range(start, end+1):
print(x)
time.sleep(1)
print("完成！")
count(30, 15)
# 15
# 16
# 17
# 18
# 19
# 20
# 21
# 22
# 23
# 24
# 25
# 26
# 27
# 28
# 29
# 30
# 完成！
32. 关键字参数 🗝️
# 关键字参数 = 在参数前加标识符的参数
# 有助于提高代码可读性
# 参数顺序无关紧要
# 1. 位置参数 2. 默认参数 3. 关键字参数 4. 任意参数
def hello(greeting, title, first, last):
print(f"{greeting} {title}{first} {last}")
hello("你好", "先生", "海绵宝宝", "方裤")
# 你好 先生海绵宝宝 方裤
hello("你好", "海绵宝宝", "方裤", "先生")
# 你好 海绵宝宝方裤 先生
hello("你好", title="先生", first="海绵宝宝", last="方裤")
# 你好 先生海绵宝宝 方裤
hello("你好", title="先生", last="方裤", first="海绵宝宝")
# 你好 先生海绵宝宝 方裤
hello(title="先生", last="方裤", first="海绵宝宝", "你好")
# SyntaxError: 位置参数不能在关键字参数之后
hello("你好", "先生", "John", "James")
# 你好 先生John James
hello("你好", title="先生", last="John", first="James")
# 你好 先生James John
--------
for x in range(1, 11):
print(x, end=" ")
# 1 2 3 4 5 6 7 8 9 10
--------
print("1", "2", "3", "4", "5", sep="-")
# 1-2-3-4-5
--------
def get_phone(country, area, first, last):
return f"{country}-{area}-{first}-{last}"
phone_num = get_phone(country=1, area=123, first=456, last=7890)
print(phone_num)
# 1-123-456-7890
33. *args 和 **kwargs 📦
# *args = 允许传递多个非关键字参数
# **kwargs = 允许传递多个关键字参数
# * 解包操作符
# 1. 位置参数 2. 默认参数 3. 关键字参数 4. 任意参数
def add(a, b):
return a + b
print(add(1, 2)) # 3
print(add(1, 2, 3))
# TypeError: add() 需要 2 个位置参数，但给定了 3 个
--------
def add(*args):
print(type(args)) # <class 'tuple'>
total = 0
for arg in args:
total += arg
return total
print(add(1, 2, 3, 4, 5)) # 15
--------
def display_name(*args):
for arg in args:
print(arg, end=" ")
display_name("博士", "海绵宝宝", "Harold", "方裤")
# 博士 海绵宝宝 Harold 方裤
--------
def print_address(**kwargs):
print(type(kwargs)) # <class 'dict'>
for value in kwargs.values():
print(value)
print_address(street="123 Fake St.",
city="底特律",
state="MI",
zip="54321")
# 123 Fake St.
# 底特律
# MI
# 54321
--------
def print_address(**kwargs):
print(type(kwargs)) # <class 'dict'>
for key in kwargs.keys():
print(key)
print_address(street="123 Fake St.",
city="底特律",
state="MI",
zip="54321")
# street
# city
# state
# zip
--------
def print_address(**kwargs):
print(type(kwargs)) # <class 'dict'>
for key, value in kwargs.items():
print(f"{key}: {value}")
print_address(street="123 Fake St.",
city="底特律",
state="MI",
zip="54321")
# street: 123 Fake St.
# city: 底特律
# state: MI
# zip: 54321
--------
def shipping_label(*args, **kwargs):
for arg in args:
print(arg, end=" ")
print()
for value in kwargs.values():
print(value, end=" ")
shipping_label("博士", "海绵宝宝", "方裤", "III",
street="123 Fake St.",
apt="100",
city="底特律",
state="MI",
zip="54321")
# 博士 海绵宝宝 方裤 III
# 123 Fake St. 100 底特律 MI 54321
--------
def shipping_label(*args, **kwargs):
for arg in args:
print(arg, end=" ")
print()
print(f"{kwargs.get('street')} {kwargs.get('apt')}")
print(f"{kwargs.get('city')} {kwargs.get('state')}, {kwargs.get('zip')}")
shipping_label("博士", "海绵宝宝", "方裤",
street="123 Fake St.",
apt="#100",
city="底特律",
state="MI",
zip="54321")
# 博士 海绵宝宝 方裤
# 123 Fake St. #100
# 底特律 MI 54321
--------
def shipping_label(*args, **kwargs):
for arg in args:
print(arg, end=" ")
print()
print(f"{kwargs.get('street')} {kwargs.get('apt')}")
print(f"{kwargs.get('city')} {kwargs.get('state')}, {kwargs.get('zip')}")
shipping_label("博士", "海绵宝宝", "方裤",
street="123 Fake St.",
city="底特律",
state="MI",
zip="54321")
# 博士 海绵宝宝 方裤
# 123 Fake St. None
# 底特律 MI 54321
--------
def shipping_label(*args, **kwargs):
for arg in args:
print(arg, end=" ")
print()
if "apt" in kwargs:
print(f"{kwargs.get('street')} {kwargs.get('apt')}")
elif "pobox" in kwargs:
print(f"{kwargs.get('street')}")
print(f"{kwargs.get('pobox')}")
else:
print(f"{kwargs.get('street')}")
print(f"{kwargs.get('city')} {kwargs.get('state')}, {kwargs.get('zip')}")
shipping_label("博士", "海绵宝宝", "方裤",
street="123 Fake St.",
pobox="PO box #1001",
city="底特律",
state="MI",
zip="54321")
# 博士 海绵宝宝 方裤
# 123 Fake St.
# PO box #1001
# 底特律 MI 54321
34. 可迭代对象 🔂
# 可迭代对象 = 一个可以逐一返回其元素的对象/集合，
# 允许在循环中进行迭代
numbers = [1, 2, 3, 4, 5]
for number in numbers:
print(number)
# 1
# 2
# 3
# 4
# 5
numbers = [1, 2, 3, 4, 5]
for number in reversed(numbers):
print(number)
# 5
# 4
# 3
# 2
# 1
numbers = [1, 2, 3, 4, 5]
for number in reversed(numbers):
print(number, end=" ")
# 5 4 3 2 1
numbers = [1, 2, 3, 4, 5]
for number in reversed(numbers):
print(number, end="-")
# 5-4-3-2-1-
numbers = [1, 2, 3, 4, 5]
for number in reversed(numbers):
print(number, end=" - ")
# 5 - 4 - 3 - 2 - 1 -
numbers = (1, 2, 3, 4, 5)
for number in numbers:
print(number)
# 1
# 2
# 3
# 4
# 5
fruits = {"apple", "orange", "banana", "coconut"}
for fruit in fruits:
print(fruit)
# apple
# orange
# banana
# coconut
fruits = {"apple", "orange", "banana", "coconut"}
for fruit in reversed(fruits):
print(fruit)
# TypeError: 'set' 对象不可反转
name ="Yuu Niji"
for character in name:
print(character)
# Y
# u
# u
#
# N
# i
# j
# i
name ="Yuu Niji"
for character in name:
print(character, end=" ")
# Y u u N i j i
my_dictionary = {"A": 1, "B": 2, "C": 3}
for key in my_dictionary:
print(key)
# A
# B
# C
my_dictionary = {"A": 1, "B": 2, "C": 3}
for value in my_dictionary.values():
print(value)
# 1
# 2
# 3
my_dictionary = {"A": 1, "B": 2, "C": 3}
for key, value in my_dictionary.items():
print(key, value)
# A 1
# B 2
# C 3
my_dictionary = {"A": 1, "B": 2, "C": 3}
for key, value in my_dictionary.items():
print(f"{key} = {value}")
# A = 1
# B = 2
# C = 3
35. 成员运算符 🔎
# 成员运算符 = 用于测试一个值或变量是否出现在一个序列中
# （字符串、列表、元组、集合或字典）
# 1. in
# 2. not in
word = "APPLE"
letter = input("猜一个秘密单词中的字母：")
if letter in word:
print(f"存在字母 {letter}")
else:
print(f"未找到字母 {letter}")
# 猜一个秘密单词中的字母：A
# 存在字母 A
# 猜一个秘密单词中的字母：Z
# 未找到字母 Z
word = "APPLE"
letter = input("猜一个秘密单词中的字母：")
if letter not in word:
print(f"未找到字母 {letter}")
else:
print(f"存在字母 {letter}")
# 猜一个秘密单词中的字母：E
# 存在字母 E
# 猜一个秘密单词中的字母：Q
# 未找到字母 Q
students = {"Spongbob", "Patrick", "Sandy"}
student = input("输入一个学生姓名：")
if student in students:
print(f"{student} 是学生")
else:
print(f"未找到学生 {student}")
# 输入一个学生姓名：Spongbob
# Spongbob 是学生
# 输入一个学生姓名：Yuuniji
# 未找到学生 Yuuniji
students = {"Spongbob", "Patrick", "Sandy"}
student = input("输入一个学生姓名：")
if student not in students:
print(f"未找到学生 {student}")
else:
print(f"{student} 是学生")
# 输入一个学生姓名：Sandy
# Sandy 是学生
# 输入一个学生姓名：Github
# 未找到学生 Github
grades = {"Sandy": "A",
"Squidward": "B",
"Spongbob": "C",
"Patrick": "D"}
student = input("输入一个学生姓名：")
if student in grades:
print(f"{student} 的成绩是 {grades[student]}")
else:
print(f"未找到学生 {student}")
# 输入一个学生姓名：Spongbob
# Spongbob 的成绩是 C
# 输入一个学生姓名：Sandy
# Sandy 的成绩是 A
# 输入一个学生姓名：Squidward
# Squidward 的成绩是 B
# 输入一个学生姓名：Patrick
# Patrick 的成绩是 D
# 输入一个学生姓名：Yuuniji
# 未找到学生 Yuuniji
email = "yuuniji81@gmail.com"
if "@" in email and "." in email:
print("有效邮箱")
else:
print("无效邮箱")
# 有效邮箱
email = "yuuniji81gmail.com"
if "@" in email and "." in email:
print("有效邮箱")
else:
print("无效邮箱")
# 无效邮箱
email = "yuuniji81@gmailcom"
if "@" in email and "." in email:
print("有效邮箱")
else:
print("无效邮箱")
# 无效邮箱
36. 列表推导 📃
# 列表推导 = Python 中创建列表的一种简洁方式
# 比传统循环更紧凑且易于阅读
# [表达式 for 值 in 可迭代对象 if 条件]
doubles = []
for x in range(1, 11):
doubles.append(x * 2)
print(doubles)
# [2, 4, 6, 8, 10, 12, 14, 16, 18, 20]
doubles = [x * 2 for x in range(1, 11)]
print(doubles)
# [2, 4, 6, 8, 10, 12, 14, 16, 18, 20]
triples = [y * 3 for y in range(1, 11)]
print(triples)
# [3, 6, 9, 12, 15, 18, 21, 24, 27, 30]
squares = [z * z for z in range(1, 11)]
print(squares)
# [1, 4, 9, 16, 25, 36, 49, 64, 81, 100]
fruits = ["apple", "orange", "banana", "coconut"]
fruits = [fruit.upper() for fruit in fruits]
print(fruits)
# ['APPLE', 'ORANGE', 'BANANA', 'COCONUT']
fruits = [fruit.upper() for fruit in ["apple", "orange", "banana", "coconut"]]
print(fruits)
# ['APPLE', 'ORANGE', 'BANANA', 'COCONUT']
fruits = ["apple", "orange", "banana", "coconut"]
fruit_chars = [fruit[0] for fruit in fruits]
print(fruit_chars)
# ['a', 'o', 'b', 'c']
numbers = [1, -2, 3, -4, 5, -6, 8, -7]
positive_nums = [num for num in numbers if num >= 0]
negative_nums = [num for num in numbers if num < 0]
even_nums = [num for num in numbers if num % 2 == 0]
odd_nums = [num for num in numbers if num % 2 == 1]
print(positive_nums)
# [1, 3, 5, 8]
print(negative_nums)
# [-2, -4, -6, -7]
print(even_nums)
# [-2, -4, -6, 8]
print(odd_nums)
# [1, 3, 5, -7]
grades = [85, 42, 79, 90, 56, 61, 30]
passing_grades = [grade for grade in grades if grade >= 60]
print(passing_grades)
# [85, 79, 90, 61]
37. match-case 语句 📆
# match-case 语句（类似 switch）：代替多个 'elif' 语句的另一种方式
# 当值匹配某个 'case' 时执行相应代码
# 优点：代码更简洁，语法更易读
def day_of_week(day):
if day == 1:
return "今天是星期日"
elif day == 2:
return "今天是星期一"
elif day == 3:
return "今天是星期二"
elif day == 4:
return "今天是星期三"
elif day == 5:
return "今天是星期四"
elif day == 6:
return "今天是星期五"
elif day == 7:
return "今天是星期六"
else:
return "不是有效的日期"
print(day_of_week(1))
# 今天是星期日
def day_of_week(day):
match day:
case 1:
return "今天是星期日"
case 2:
return "今天是星期一"
case 3:
return "今天是星期二"
case 4:
return "今天是星期三"
case 5:
return "今天是星期四"
case 6:
return "今天是星期五"
case 7:
return "今天是星期六"
case _: # _ = 通配符
return "不是有效的日期"
print(day_of_week(1))
# 今天是星期日
def is_weekend(day):
match day:
case "Sunday":
return True
case "Monday":
return False
case "Tuesday":
return False
case "Wednesday":
return False
case "Thursday":
return False
case "Friday":
return False
case "Saturday":
return True
case _: # _ = 通配符
return False
print(is_weekend("Sunday"))
# True
def is_weekend(day):
match day:
case "Saturday" | "Sunday": # | = 或
return True
case "Monday" | "Tuesday" | "Wednesday" | "Thursday" | "Friday":
return False
case _: # _ = 通配符
return False
print(is_weekend("Sunday"))
# True
38. 模块 📨
# 模块 = 包含你想在程序中使用的代码文件
# 使用 'import' 引入模块（内置或自定义）
# 有助于将大型程序分解为可重用的独立文件
# print(help("modules"))
# print(help("math"))
import math
print(math.pi)
# 3.141592653589794
import math as m
print(math.pi)
# NameError: name 'math' is not defined
import math as m
print(m.pi)
# 3.141592653589794
from math import pi
print(pi)
# 3.141592653589794
from math import e
print(e)
# 2.718281828459045
from math import e
a, b, c, d = 1, 2, 3, 4
print(e ** a)
print(e ** b)
print(e ** c)
print(e ** d)
# 2.718281828459045
# 7.3890560989306495
# 20.085536923187664
# 54.5915003314423
from math import e
a, b, c, d, e = 1, 2, 3, 4, 5
print(e ** a)
print(e ** b)
print(e ** c)
print(e ** d)
print(e ** e)
# 2.718281828459045
# 7.3890560989306495
# 20.085536923187664
# 54.5915003314423
# 148.41315910257657
# example.py
pi = 3.14159
def square(x):
return x ** 2
def cube(x):
return x ** 3
def circumference(radius):
return 2 * pi * radius
def area(radius):
return pi * radius ** 2
# main.py
import example
result = example.pi
print(result)
# 3.14159
import example
result = example.square(3)
print(result) # 9
import example
result = example.cube(3)
print(result)
# 27
import example
result = example.circumference(3)
print(result)
# 18.849539999999998
import example
result = example.area(3)
print(result)
# 28.27431
39. 作用域解析 🔬
# 变量作用域 = 变量可见和可访问的范围
# 作用域解析 = (LEGB) 局部 -> 闭包 -> 全局 -> 内置
def func1():
a = 1
print(a)
def func2():
b = 2
print(b)
func1() # 1
func2() # 2
def func1():
a = 1
print(b)
def func2():
b = 2
print(a)
func1()
func2()
# NameError: 名称 'b' 未定义
def happy_birthday(name, age):
print(f"亲爱的 {name}，生日快乐")
print(f"你今年 {age} 岁")
def main():
name = "Yuuniji"
age = 21
happy_birthday(name, age)
main()
def func1():
x = 1
print(x)
def func2():
x = 2
print(x)
func1() # 1
func2() # 2
def func1():
x = 1
def func2():
x = 2
print(x)
func2()
func1()
# 2
def func1():
x = 1
def func2():
print(x)
func2()
func1()
# 1
def func1():
print(x)
def func2():
print(x)
x = 3
func1() # 3
func2() # 3
def func1():
x = 1
print(x)
def func2():
x = 2
print(x)
x = 3
func1() # 1
func2() # 2
from math import e
print(e)
# 2.718281828459045
from math import e
def func1():
print(e)
func1()
# 2.718281828459045
from math import e
def func1():
print(e)
e = 3
func1()
# 3
40. if name == ‘main’: 📥
# if __name__ == '__main__': （此脚本可以被导入或独立运行）
# 模块中的函数和类可以被重用，而主代码块不会执行
# 最佳实践（代码模块化，
# 提高可读性，
# 避免全局变量，
# 防止意外执行）
# 示例：library = 导入库以使用功能
# 直接运行库时，显示帮助页面
def main():
# 你的程序代码在这里
if __name__ == '__main__':
main()
# script1.py
# print(dir())
print(__name__)
# __main__
# script1.py
from script2 import *
# 当 script2.py 被 script1.py 导入时，它被视为一个模块，而不是主脚本。因此，Python 将其 __name__ 设置为模块名称，即 "script2"（文件名，不含 .py 扩展名）。
# 在 script2.py 中的 print(__name__) 语句会在导入过程中执行，打印 "script2"。
print(__name__)
# script2
# __main__
# script1.py
print(__name__)
# script2
# __main__
--------
# script2.py
from script1 import *
print(__name__)
# script1
# __main__
# script1.py
def favorite_food(food):
print(f"你最喜欢的食物是 {food}")
def main():
print("这是 script1")
favorite_food("披萨")
print("再见！")
if __name__ == '__main__':
main()
# 这是 script1
# 你最喜欢的食物是披萨
# 再见！
--------
# script2.py
from script1 import *
#
# script1.py
def favorite_food(food):
print(f"你最喜欢的食物是 {food}")
print("这是 script1")
favorite_food("披萨")
print("再见！")
--------
# script2.py
from script1 import *
# 这是 script1
# 你最喜欢的食物是披萨
# 再见！
# script1.py
def favorite_food(food):
print(f"你最喜欢的食物是 {food}")
def main():
print("这是 script1")
favorite_food("披萨")
print("再见！")
if __name__ == '__main__':
main()
--------
# script2.py
from script1 import *
def favorite_drink(drink):
print(f"你最喜欢的饮料是 {drink}")
print("这是 script2")
favorite_food("寿司")
favorite_drink("咖啡")
print("再见！")
# 这是 script2
# 你最喜欢的食物是寿司
# 你最喜欢的饮料是咖啡
# 再见！
# script1.py
def favorite_food(food):
print(f"你最喜欢的食物是 {food}")
def main():
print("这是 script1")
favorite_food("披萨")
print("再见！")
if __name__ == '__main__':
main()
--------
# script2.py
from script1 import *
def favorite_drink(drink):
print(f"你最喜欢的饮料是 {drink}")
def main():
print("这是 script2")
favorite_food("寿司")
favorite_drink("咖啡")
print("再见！")
if __name__ == '__main__':
main()
# 这是 script2
# 你最喜欢的食物是寿司
# 你最喜欢的饮料是咖啡
# 再见！
41. ⭐ 银行程序 💰
# Python 银行程序
# 1. 显示余额
# 2. 存款
# 3. 取款
def show_balance():
pass
def deposit():
pass
def withdraw():
pass
balance = 0
is_running = True
while is_running:
print("银行程序")
print("1. 显示余额")
print("2. 存款")
print("3. 取款")
print("4. 退出")
choice = input("请输入您的选择 (1-4): ")
if choice == '1':
show_balance()
elif choice == '2':
deposit()
elif choice == '3':
withdraw()
elif choice == '4':
is_running = False
else:
print("无效的选择")
print("谢谢！祝您有愉快的一天！")
# 银行程序
# 1. 显示余额
# 2. 存款
# 3. 取款
# 4. 退出
# 请输入您的选择 (1-4): 1
# 银行程序
# 1. 显示余额
# 2. 存款
# 3. 取款
# 4. 退出
# 请输入您的选择 (1-4): 4
# 谢谢！祝您有愉快的一天！
def show_balance():
print(f"您的余额为 ${balance:.2f}")
def deposit():
amount = float(input("请输入存款金额: "))
if amount < 0:
print("无效的金额")
else:
return amount
def withdraw():
pass
balance = 0
is_running = True
while is_running:
print("银行程序")
print("1. 显示余额")
print("2. 存款")
print("3. 取款")
print("4. 退出")
choice = input("请输入您的选择 (1-4): ")
if choice == '1':
show_balance()
elif choice == '2':
balance += deposit()
elif choice == '3':
withdraw()
elif choice == '4':
is_running = False
else:
print("无效的选择")
print("谢谢！祝您有愉快的一天！")
# 银行程序
# 1. 显示余额
# 2. 存款
# 3. 取款
# 4. 退出
# 请输入您的选择 (1-4): 1
# 您的余额为 $0.00
# 银行程序
# 1. 显示余额
# 2. 存款
# 3. 取款
# 4. 退出
# 请输入您的选择 (1-4): 2
# 请输入存款金额: 100
# 银行程序
# 1. 显示余额
# 2. 存款
# 3. 取款
# 4. 退出
# 请输入您的选择 (1-4): 1
# 您的余额为 $100.00
# 银行程序
# 1. 显示余额
# 2. 存款
# 3. 取款
# 4. 退出
# 请输入您的选择 (1-4): 2
# 请输入存款金额: -420.69
# 无效的金额
# TypeError: 不支持的操作数类型 +=: 'float' 和 'NoneType'
def show_balance():
print(f"您的余额为 ${balance:.2f}")
def deposit():
amount = float(input("请输入存款金额: "))
if amount < 0:
print("无效的金额")
return 0
else:
return amount
def withdraw():
pass
balance = 0
is_running = True
while is_running:
print("银行程序")
print("1. 显示余额")
print("2. 存款")
print("3. 取款")
print("4. 退出")
choice = input("请输入您的选择 (1-4): ")
if choice == '1':
show_balance()
elif choice == '2':
balance += deposit()
elif choice == '3':
withdraw()
elif choice == '4':
is_running = False
else:
print("无效的选择")
print("谢谢！祝您有愉快的一天！")
# 银行程序
# 1. 显示余额
# 2. 存款
# 3. 取款
# 4. 退出
# 请输入您的选择 (1-4): 2
# 请输入存款金额: -420.69
# 无效的金额
# 银行程序
# 1. 显示余额
# 2. 存款
# 3. 取款
# 4. 退出
# 请输入您的选择 (1-4): 2
# 请输入存款金额: 50.01
# 银行程序
# 1. 显示余额
# 2. 存款
# 3. 取款
# 4. 退出
# 请输入您的选择 (1-4): 1
# 您的余额为 $50.01
def show_balance():
print(f"您的余额为 ${balance:.2f}")
def deposit():
amount = float(input("请输入存款金额: "))
if amount < 0:
print("无效的金额")
return 0
else:
return amount
def withdraw():
amount = float(input("请输入取款金额: "))
if amount > balance:
print("余额不足")
return 0
elif amount < 0:
print("金额必须大于0")
return 0
else:
return amount
balance = 0
is_running = True
while is_running:
print("银行程序")
print("1. 显示余额")
print("2. 存款")
print("3. 取款")
print("4. 退出")
choice = input("请输入您的选择 (1-4): ")
if choice == '1':
show_balance()
elif choice == '2':
balance += deposit()
elif choice == '3':
balance -= withdraw()
elif choice == '4':
is_running = False
else:
print("无效的选择")
print("谢谢！祝您有愉快的一天！")
# 银行程序
# 1. 显示余额
# 2. 存款
# 3. 取款
# 4. 退出
# 请输入您的选择 (1-4): 1
# 您的余额为 $0.00
# 银行程序
# 1. 显示余额
# 2. 存款
# 3. 取款
# 4. 退出
# 请输入您的选择 (1-4): 2
# 请输入存款金额: 100
# 银行程序
# 1. 显示余额
# 2. 存款
# 3. 取款
# 4. 退出
# 请输入您的选择 (1-4): 1
# 您的余额为 $100.00
# 银行程序
# 1. 显示余额
# 2. 存款
# 3. 取款
# 4. 退出
# 请输入您的选择 (1-4): 3
# 请输入取款金额: 1000000000000000000000
# 余额不足
# 银行程序
# 1. 显示余额
# 2. 存款
# 3. 取款
# 4. 退出
# 请输入您的选择 (1-4): 3
# 请输入取款金额: -420.69
# 金额必须大于0
# 银行程序
# 1. 显示余额
# 2. 存款
# 3. 取款
# 4. 退出
# 请输入您的选择 (1-4): 3
# 请输入取款金额: -49.99
# 金额必须大于0
# 银行程序
# 1. 显示余额
# 2. 存款
# 3. 取款
# 4. 退出
# 请输入您的选择 (1-4): 1
# 您的余额为 $50.01
# 银行程序
# 1. 显示余额
# 2. 存款
# 3. 取款
# 4. 退出
# 请输入您的选择 (1-4): 4
# 谢谢！祝您有愉快的一天！
def show_balance(balance):
print("*********************")
print(f"您的余额为 ${balance:.2f}")
print("*********************")
def deposit():
print("*********************")
amount = float(input("请输入存款金额: "))
print("*********************")
if amount < 0:
print("*********************")
print("无效的金额")
print("*********************")
return 0
else:
return amount
def withdraw(balance):
print("*********************")
amount = float(input("请输入取款金额: "))
print("*********************")
if amount > balance:
print("*********************")
print("余额不足")
print("*********************")
return 0
elif amount < 0:
print("*********************")
print("金额必须大于0")
print("*********************")
return 0
else:
return amount
def main():
balance = 0
is_running = True
while is_running:
print("*********************")
print(" 银行程序 ")
print("*********************")
print("1. 显示余额")
print("2. 存款")
print("3. 取款")
print("4. 退出")
print("*********************")
choice = input("请输入您的选择 (1-4): ")
if choice == '1':
show_balance(balance)
elif choice == '2':
balance += deposit()
elif choice == '3':
balance -= withdraw(balance)
elif choice == '4':
is_running = False
else:
print("*********************")
print("无效的选择")
print("*********************")
print("*********************")
print("谢谢！祝您有愉快的一天！")
print("*********************")
if __name__ == '__main__':
main()
# *********************
# 银行程序
# *********************
# 1. 显示余额
# 2. 存款
# 3. 取款
# 4. 退出
# *********************
# 请输入您的选择 (1-4): 1
# *********************
# 您的余额为 $0.00
# *********************
# *********************
# 银行程序
# *********************
# 1. 显示余额
# 2. 存款
# 3. 取款
# 4. 退出
# *********************
# 请输入您的选择 (1-4): 2
# *********************
# 请输入存款金额: 100.01
# *********************
# *********************
# 银行程序
# *********************
# 1. 显示余额
# 2. 存款
# 3. 取款
# 4. 退出
# *********************
# 请输入您的选择 (1-4): 1
# *********************
# 您的余额为 $100.01
# *********************
# *********************
# 银行程序
# *********************
# 1. 显示余额
# 2. 存款
# 3. 取款
# 4. 退出
# *********************
# 请输入您的选择 (1-4): 3
# 请输入取款金额: 1000
# *********************
# 余额不足
# *********************
# *********************
# 银行程序
# *********************
# 1. 显示余额
# 2. 存款
# 3. 取款
# 4. 退出
# *********************
# 请输入您的选择 (1-4): 3
# 请输入取款金额: 50
# *********************
# 银行程序
# *********************
# 1. 显示余额
# 2. 存款
# 3. 取款
# 4. 退出
# *********************
# 请输入您的选择 (1-4): 1
# *********************
# 您的余额为 $50.01
# *********************
# *********************
# 银行程序
# *********************
# 1. 显示余额
# 2. 存款
# 3. 取款
# 4. 退出
# *********************
# 请输入您的选择 (1-4): 4
# *********************
# 谢谢！祝您有愉快的一天！
# *********************
42. ⭐ 老虎机 🎰
# Python 老虎机
def spin_row():
pass
def print_row():
pass
def get_payout():
pass
def main():
pass
if __name__ == '__main__':
main()
def spin_row():
pass
def print_row():
pass
def get_payout():
pass
def main():
balance = 100
print("*************************")
print("欢迎体验 Python 老虎机")
print("符号：🍒 🍉 🍋 🔔 ⭐️")
print("*************************")
while balance > 0:
print(f"当前余额：${balance}")
bet = input("请输入您的下注金额：")
if not bet.isdigit():
print("请输入有效的数字")
continue
bet = int(bet)
if bet > balance:
print("余额不足")
continue
if bet < 0:
print("下注金额必须大于 0")
continue
balance -= bet
if __name__ == '__main__':
main()
# *************************
# 欢迎体验 Python 老虎机
# 符号：🍒 🍉 🍋 🔔 ⭐️
# *************************
# 当前余额：$100
# 请输入您的下注金额：pizza
# 请输入有效的数字
# 当前余额：$100
# 请输入您的下注金额：10000000000000000
# 余额不足
# 当前余额：$100
# 请输入您的下注金额：0
# 下注金额必须大于 0
# 当前余额：$100
# 请输入您的下注金额：1
# 当前余额：$99
# 请输入您的下注金额：10
# 当前余额：$89
# 请输入您的下注金额：90
# 余额不足
# 当前余额：$89
# 请输入您的下注金额：89
import random
def spin_row():
symbols = ['🍒', '🍉', '🍋', '🔔', '⭐️']
# results = []
# for _ in range(3):
# results.append(random.choice(symbols))
# return results
return [random.choice(symbols) for _ in range(3)]
# return [random.choice(symbols) for symbols in range(3)]
def print_row():
pass
def get_payout():
pass
def main():
balance = 100
print("*************************")
print("欢迎体验 Python 老虎机")
print("符号：🍒 🍉 🍋 🔔 ⭐️")
print("*************************")
while balance > 0:
print(f"当前余额：${balance}")
bet = input("请输入您的下注金额：")
if not bet.isdigit():
print("请输入有效的数字")
continue
bet = int(bet)
if bet > balance:
print("余额不足")
continue
if bet < 0:
print("下注金额必须大于 0")
continue
balance -= bet
row = spin_row()
print(row)
if __name__ == '__main__':
main()
# *************************
# 欢迎体验 Python 老虎机
# 符号：🍒 🍉 🍋 🔔 ⭐️
# *************************
# 当前余额：$100
# 请输入您的下注金额：1
# ['⭐️', '🍋', '🍋']
# 当前余额：$99
# 请输入您的下注金额：1
# ['🍉', '🍒', '⭐️']
# 当前余额：$98
# 请输入您的下注金额：1
# ['🍒', '🍉', '🍒']
# 当前余额：$97
# 请输入您的下注金额：1
# ['⭐️', '🍋', '⭐️']
# 当前余额：$96
# 请输入您的下注金额：1
# ['🍋', '🍒', '🍋']
# 当前余额：$95
# 请输入您的下注金额：
import random
def spin_row():
symbols = ['🍒', '🍉', '🍋', '🔔', '⭐️']
# results = []
# for _ in range(3):
# results.append(random.choice(symbols))
# return results
return [random.choice(symbols) for _ in range(3)]
# return [random.choice(symbols) for symbols in range(3)]
def print_row(row):
print(" ".join(row))
def get_payout():
pass
def main():
balance = 100
print("*************************")
print("欢迎体验 Python 老虎机")
print("符号：🍒 🍉 🍋 🔔 ⭐️")
print("*************************")
while balance > 0:
print(f"当前余额：${balance}")
bet = input("请输入您的下注金额：")
if not bet.isdigit():
print("请输入有效的数字")
continue
bet = int(bet)
if bet > balance:
print("余额不足")
continue
if bet < 0:
print("下注金额必须大于 0")
continue
balance -= bet
row = spin_row()
print("旋转中...\n")
print_row(row)
if __name__ == '__main__':
main()
# *************************
# 欢迎体验 Python 老虎机
# 符号：🍒 🍉 🍋 🔔 ⭐️
# *************************
# 当前余额：$100
# 请输入您的下注金额：1
# 旋转中...
#
# 🍋 ⭐️ 🔔
# 当前余额：$99
# 请输入您的下注金额：
import random
def spin_row():
symbols = ['🍒', '🍉', '🍋', '🔔', '⭐️']
# results = []
# for _ in range(3):
# results.append(random.choice(symbols))
# return results
return [random.choice(symbols) for _ in range(3)]
# return [random.choice(symbols) for symbols in range(3)]
def print_row(row):
print("*************")
print(" | ".join(row))
print("*************")
def get_payout():
pass
def main():
balance = 100
print("*************************")
print("欢迎体验 Python 老虎机")
print("符号：🍒 🍉 🍋 🔔 ⭐️")
print("*************************")
while balance > 0:
print(f"当前余额：${balance}")
bet = input("请输入您的下注金额：")
if not bet.isdigit():
print("请输入有效的数字")
continue
bet = int(bet)
if bet > balance:
print("余额不足")
continue
if bet < 0:
print("下注金额必须大于 0")
continue
balance -= bet
row = spin_row()
print("旋转中...\n")
print_row(row)
if __name__ == '__main__':
main()
# *************************
# 欢迎体验 Python 老虎机
# 符号：🍒 🍉 🍋 🔔 ⭐️
# *************************
# 当前余额：$100
# 请输入您的下注金额：1
# 旋转中...
#
# *************
# 🔔 | 🍉 | ⭐️
# *************
# 当前余额：$99
# 请输入您的下注金额：2
# 旋转中...
#
# *************
# 🍒 | 🍒 | 🔔
# *************
# 当前余额：$97
# 请输入您的下注金额：3
# 旋转中...
#
# *************
# 🍒 | ⭐️ | ⭐️
# *************
# 当前余额：$94
# 请输入您的下注金额：4
# 旋转中...
#
# *************
# 🍉 | 🍉 | 🍉
# *************
# 当前余额：$90
# 请输入您的下注金额：
import random
def spin_row():
symbols = ['🍒', '🍉', '🍋', '🔔', '⭐️']
# results = []
# for _ in range(3):
# results.append(random.choice(symbols))
# return results
return [random.choice(symbols) for _ in range(3)]
# return [random.choice(symbols) for symbols in range(3)]
def print_row(row):
print("*************")
print(" | ".join(row))
print("*************")
def get_payout(row, bet):
if row[0] == row[1] == row[2]:
if row[0] == '🍒':
return bet * 3
elif row[0] == '🍉':
return bet * 4
elif row[0] == '🍋':
return bet * 5
elif row[0] == '🔔':
return bet * 10
elif row[0] == '⭐️':
return bet * 20
return 0
def main():
balance = 100
print("*************************")
print("欢迎体验 Python 老虎机")
print("符号：🍒 🍉 🍋 🔔 ⭐️")
print("*************************")
while balance > 0:
print(f"当前余额：${balance}")
bet = input("请输入您的下注金额：")
if not bet.isdigit():
print("请输入有效的数字")
continue
bet = int(bet)
if bet > balance:
print("余额不足")
continue
if bet < 0:
print("下注金额必须大于 0")
continue
balance -= bet
row = spin_row()
print("旋转中...\n")
print_row(row)
payout = get_payout(row, bet)
if payout > 0:
print(f"您赢得了 ${payout}")
else:
print("很遗憾，您本轮未获胜")
balance += payout
if __name__ == '__main__':
main()
# *************************
# 欢迎体验 Python 老虎机
# 符号：🍒 🍉 🍋 🔔 ⭐️
# *************************
# 当前余额：$100
# 请输入您的下注金额：1
# 旋转中...
#
# *************
# 🔔 | 🍉 | ⭐️
# *************
# 很遗憾，您本轮未获胜
# 当前余额：$99
# 请输入您的下注金额：2
# 旋转中...
#
# *************
# 🍒 | 🍒 | 🔔
# *************
# 很遗憾，您本轮未获胜
# 当前余额：$97
# 请输入您的下注金额：3
# 旋转中...
#
# *************
# 🍒 | ⭐️ | ⭐️
# *************
# 很遗憾，您本轮未获胜
# 当前余额：$94
# 请输入您的下注金额：1
# 旋转中...
#
# *************
# 🍉 | 🍉 | 🍉
# *************
# 您赢得了 $4
# 当前余额：$93
# 请输入您的下注金额：
import random
def spin_row():
symbols = ['🍒', '🍉', '🍋', '🔔', '⭐️']
# results = []
# for _ in range(3):
# results.append(random.choice(symbols))
# return results
return [random.choice(symbols) for _ in range(3)]
# return [random.choice(symbols) for symbols in range(3)]
def print_row(row):
print("*************")
print(" | ".join(row))
print("*************")
def get_payout(row, bet):
if row[0] == row[1] == row[2]:
if row[0] == '🍒':
return bet * 3
elif row[0] == '🍉':
return bet * 4
elif row[0] == '🍋':
return bet * 5
elif row[0] == '🔔':
return bet * 10
elif row[0] == '⭐️':
return bet * 20
return 0
def main():
balance = 100
print("*************************")
print("欢迎体验 Python 老虎机")
print("符号：🍒 🍉 🍋 🔔 ⭐️")
print("*************************")
while balance > 0:
print(f"当前余额：${balance}")
bet = input("请输入您的下注金额：")
if not bet.isdigit():
print("请输入有效的数字")
continue
bet = int(bet)
if bet > balance:
print("余额不足")
continue
if bet < 0:
print("下注金额必须大于 0")
continue
balance -= bet
row = spin_row()
print("旋转中...\n")
print_row(row)
payout = get_payout(row, bet)
if payout > 0:
print(f"您赢得了 ${payout}")
else:
print("很遗憾，您本轮未获胜")
balance += payout
play_again = input("您想再次旋转吗？(Y/N)：").upper()
if play_again != 'Y':
break
print("*******************************************")
print(f"游戏结束！您的最终余额为 ${balance}")
print("*******************************************")
if __name__ == '__main__':
main()
# *************************
# 欢迎体验 Python 老虎机
# 符号：🍒 🍉 🍋 🔔 ⭐️
# *************************
# 当前余额：$100
# 请输入您的下注金额：1
# 旋转中...
#
# *************
# 🔔 | 🍉 | ⭐️
# *************
# 很遗憾，您本轮未获胜
# 您想再次旋转吗？(Y/N)：y
# 当前余额：$99
# 请输入您的下注金额：5
# 旋转中...
#
# *************
# 🍒 | 🍒 | 🔔
# *************
# 很遗憾，您本轮未获胜
# 您想再次旋转吗？(Y/N)：y
# 当前余额：$94
# 请输入您的下注金额：90
# 旋转中...
#
# *************
# 🍒 | ⭐️ | ⭐️
# *************
# 很遗憾，您本轮未获胜
# 您想再次旋转吗？(Y/N)：y
# 当前余额：$4
# 请输入您的下注金额：1
# 旋转中...
#
# *************
# 🔔 | 🔔 | 🔔
# *************
# 您赢得了 $10
# 您想再次旋转吗？(Y/N)：n
# ******************************************
# 游戏结束！您的最终余额为 $14
# ******************************************
43. ⭐ 加密程序 🔐
import string
# chars = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
chars = " " + string.punctuation + string.digits + string.ascii_letters
print(chars)
# !"#$%&'()*+,-./:;<=>?@[\]^_`{|}~0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ
import string
chars = " " + string.punctuation + string.digits + string.ascii_letters
chars = list(chars)
print(chars)
# [' ', '!', '"', '#', '$', '%', '&', "'", '(', ')', '*', '+', ',', '-', '.', '/', ':', ';', '<', '=', '>', '?', '@', '[', '\\', ']', '^', '_', '`', '{', '|', '}', '~', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z']
import string
chars = " " + string.punctuation + string.digits + string.ascii_letters
chars = list(chars)
key = chars.copy()
print(f"字符集: {chars}")
print(f"密钥 : {key}")
# 字符集: [' ', '!', '"', '#', '$', '%', '&', "'", '(', ')', '*', '+', ',', '-', '.', '/', ':', ';', '<', '=', '>', '?', '@', '[', '\\', ']', '^', '_', '`', '{', '|', '}', '~', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z']
# 密钥 : [' ', '!', '"', '#', '$', '%', '&', "'", '(', ')', '*', '+', ',', '-', '.', '/', ':', ';', '<', '=', '>', '?', '@', '[', '\\', ']', '^', '_', '`', '{', '|', '}', '~', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z']
import random
import string
chars = " " + string.punctuation + string.digits + string.ascii_letters
chars = list(chars)
key = chars.copy()
random.shuffle(key)
print(f"字符集: {chars}")
print(f"密钥 : {key}")
# 字符集: [' ', '!', '"', '#', '$', '%', '&', "'", '(', ')', '*', '+', ',', '-', '.', '/', ':', ';', '<', '=', '>', '?', '@', '[', '\\', ']', '^', '_', '`', '{', '|', '}', '~', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z']
# 密钥 : ['k', '9', 'V', '=', '!', 'K', 'q', 'w', 'O', '}', 'Y', 'S', 'B', '*', 'm', '(', '[', 'G', '>', ' ', 'N', '^', ']', 'u', 'H', '/', 'l', 'z', 'v', 'c', ';', 'p', '_', 'M', '#', 'r', '3', 'J', 'e', 'D', 'I', '&', '2', '1', 'W', 't', 'j', '@', 'h', '6', 'i', '0', 'y', '.', 'Z', 'U', 'P', 'A', 'd', 'n', 'T', '4', 'E', 'x', 'Q', '7', 'f', '-', '"', 'o', 'b', '8', '|', '$', '~', 'C', 'X', 'R', ':', 'g', '?', ')', '+', 'F', '{', 's', '5', ',', 'L', '`', '%', 'a', '<', '\\', "'", 'T']
import random
import string
chars = " " + string.punctuation + string.digits + string.ascii_letters
chars = list(chars)
key = chars.copy()
random.shuffle(key)
print(f"字符集: {chars}")
print(f"密钥 : {key}")
# 加密
plain_text = input("请输入要加密的消息: ")
cipher_text = ""
for letter in plain_text:
index = chars.index(letter)
cipher_text += key[index]
print(f"原始消息: {plain_text}")
print(f"加密消息: {cipher_text}")
# 请输入要加密的消息: I like pizza!
# 字符集: [' ', '!', '"', '#', '$', '%', '&', "'", '(', ')', '*', '+', ',', '-', '.', '/', ':', ';', '<', '=', '>', '?', '@', '[', '\\', ']', '^', '_', '`', '{', '|', '}', '~', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z']
# 密钥 : ['k', '9', 'V', '=', '!', 'K', 'q', 'w', 'O', '}', 'Y', 'S', 'B', '*', 'm', '(', '[', 'G', '>', 'R', ']', 'u', 'H', '/', 'l', 'z', 'c', ';', 'p', '_', 'M', '#', 'T', '4', '1', '2', '3', '0', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'y', 'L', 'x', 'n', 'o', 'p', 'q', 'r', 's', 't', 'A', 'v', 'W', 'X', 'Z', 't', 'J', 'C', 'P', 'Q', 'U', 'E', 'F', 'I', 'D', 'N', 'B', 'y', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z']
# 原始消息: I like pizza!
# 加密消息: D Liye piJJa9
import random
import string
chars = " " + string.punctuation + string.digits + string.ascii_letters
chars = list(chars)
key = chars.copy()
random.shuffle(key)
# print(f"字符集: {chars}")
# print(f"密钥 : {key}")
# 加密
plain_text = input("请输入要加密的消息: ")
cipher_text = ""
for letter in plain_text:
index = chars.index(letter)
cipher_text += key[index]
print(f"原始消息: {plain_text}")
print(f"加密消息: {cipher_text}")
# 解密
cipher_text = input("请输入要解密的消息: ")
plain_text = ""
for letter in cipher_text:
index = key.index(letter)
plain_text += chars[index]
print(f"加密消息: {cipher_text}")
print(f"原始消息: {plain_text}")
# 请输入要加密的消息: I like pizza!
# 原始消息: I like pizza!
# 加密消息: NkLiyekpiJJa9
# 请输入要解密的消息: NkLiyekpiJJa9
# 加密消息: NkLiyekpiJJa9
# 原始消息: I like pizza!
44. ⭐ 猜字游戏 🕺
# Python 猜字游戏
import random
words = ("apple", "orange", "banana", "coconut", "pineapple")
# 键值对字典，用于存储不同错误次数对应的图形
hangman_art = {0: (" ",
" ",
" "),
1: (" o ",
" ",
" ",
" "),
2: (" o ",
" | ",
" "),
3: (" o ",
"/| ",
" "),
4: (" o ",
"/|\\",
" "),
5: (" o ",
"/|\\",
"/ "),
6: (" o ",
"/|\\",
"/ \\")}
# 示例：打印错误次数为3时的图形
# print(hangman_art[3])
# (' o ', '/| ', ' ')
for line in hangman_art[3]:
print(line)
# o
# /|
#
import random
words = ("apple", "orange", "banana", "coconut", "pineapple")
# 键值对字典，用于存储不同错误次数对应的图形
hangman_art = {0: (" ",
" ",
" "),
1: (" o ",
" ",
" ",
" "),
2: (" o ",
" | ",
" "),
3: (" o ",
"/| ",
" "),
4: (" o ",
"/|\\",
" "),
5: (" o ",
"/|\\",
"/ "),
6: (" o ",
"/|\\",
"/ \\")}
def display_man(wrong_guesses):
print("**********")
for line in hangman_art[wrong_guesses]:
print(line)
print("**********")
def display_hint(hint):
pass
def display_answer(answer):
pass
def main():
answer = random.choice(words)
# print(answer)
# apple
hint = ["_"] * len(answer)
# print(hint)
# ['_', '_', '_', '_', '_']
wrong_guesses = 6
guessed_letters = set()
is_running = True
while is_running:
display_man(wrong_guesses)
display_hint(hint)
guess = input("请输入一个字母：").lower()
if __name__ == '__main__':
main()
# **********
# o
# /|\
# / \
# **********
# 请输入一个字母：
# wordslist.py
words = ("apple", "orange", "banana", "coconut", "pineapple")
# main.py
from wordslist import words
import random
# 键值对字典，用于存储不同错误次数对应的图形
hangman_art = {0: (" ",
" ",
" "),
1: (" o ",
" ",
" ",
" "),
2: (" o ",
" | ",
" "),
3: (" o ",
"/| ",
" "),
4: (" o ",
"/|\\",
" "),
5: (" o ",
"/|\\",
"/ "),
6: (" o ",
"/|\\",
"/ \\")}
def display_man(wrong_guesses):
print("**********")
for line in hangman_art[wrong_guesses]:
print(line)
print("**********")
def display_hint(hint):
print(" ".join(hint))
def display_answer(answer):
print(" ".join(answer))
def main():
answer = random.choice(words)
hint = ["_"] * len(answer)
wrong_guesses = 0
guessed_letters = set()
is_running = True
while is_running:
display_man(wrong_guesses)
display_hint(hint)
guess = input("请输入一个字母：").lower()
if len(guess) != 1 or not guess.isalpha():
print("输入无效")
continue
if guess in guessed_letters:
print(f"{guess} 已经被猜过了")
continue
guessed_letters.add(guess)
if guess in answer:
for i in range(len(answer)):
if answer[i] == guess:
hint[i] = guess
else:
wrong_guesses += 1
if "_" not in hint:
display_man(wrong_guesses)
display_answer(answer)
print("你赢了！")
is_running = False
elif wrong_guesses >= len(hangman_art) - 1:
display_man(wrong_guesses)
display_answer(answer)
print("你输了！")
is_running = False
if __name__ == '__main__':
main()
# **********
#
#
#
# **********
# _ _ _ _ _ _ _ _ _
# 请输入一个字母：p
# **********
#
#
#
# **********
# p _ _ _ _ p p _ _
# 请输入一个字母：&
# 输入无效
# **********
#
#
#
# **********
# p _ _ _ _ p p _ _
# 请输入一个字母：i
# **********
#
#
#
# **********
# p i _ _ _ p p _ _
# 请输入一个字母：n
# **********
#
#
#
# **********
# p i n _ _ p p _ _
# 请输入一个字母：p
# p 已经被猜过了
# **********
#
#
#
# **********
# p i n _ _ p p _ _
# 请输入一个字母：x
# **********
# o
#
#
#
# **********
# p i n _ _ p p _ _
# 请输入一个字母：z
# **********
# o
# |
#
# **********
# p i n _ _ p p _ _
# 请输入一个字母：e
# **********
# o
# |
#
# **********
# p i n e _ p p _ e
# 请输入一个字母：a
# **********
# o
# |
#
# **********
# p i n e a p p _ e
# 请输入一个字母：l
# **********
# o
# |
#
# **********
# p i n e a p p l e
# 你赢了！
45. Python 面向对象编程 🚗
object（对象） = 相关属性（变量）和方法（函数）的“捆绑”
示例：手机、杯子、书籍
需要使用“类”来创建多个对象
class（类） = （蓝图）用于设计对象的结构和布局
class Car:
def __init__(self, model, year, color, for_sale):
self.model = model
self.year = year
self.color = color
self.for_sale = for_sale
car1 = Car("Mustang", 2024, "red", False)
print(car1)
# <__main__.Car object at 0x000001AE490AE610>
print(car1.model)
# Mustang
print(car1.year)
# 2024
print(car1.color)
# red
print(car1.for_sale)
# False
# car.py
class Car:
def __init__(self, model, year, color, for_sale):
self.model = model
self.year = year
self.color = color
self.for_sale = for_sale
# main.py
from car import Car
car1 = Car("Mustang", 2024, "red", False)
car2 = Car("Corvette", 2025, "blue", True)
car3 = Car("Charger", 2026, "yellow", True)
print(car1.model)
# Mustang
print(car1.year)
# 2024
print(car1.color)
# red
print(car1.for_sale)
# False
# car.py
class Car:
def __init__(self, model, year, color, for_sale):
self.model = model
self.year = year
self.color = color
self.for_sale = for_sale
def drive(self):
print("你正在驾驶汽车")
def stop(self):
print("你停下了汽车")
# main.py
from car import Car
car1 = Car("Mustang", 2024, "red", False)
car2 = Car("Corvette", 2025, "blue", True)
car3 = Car("Charger", 2026, "yellow", True)
car1.drive()
# 你正在驾驶汽车
car2.drive()
# 你正在驾驶汽车
car1.stop()
# 你停下了汽车
car2.stop()
# 你停下了汽车
# car.py
class Car:
def __init__(self, model, year, color, for_sale):
self.model = model
self.year = year
self.color = color
self.for_sale = for_sale
def drive(self):
print(f"你正在驾驶 {self.color} {self.model}")
def stop(self):
print(f"你停下了 {self.color} {self.model}")
def describe(self):
print(f"{self.year} {self.color} {self.model}")
# main.py
from car import Car
car1 = Car("Mustang", 2024, "red", False)
car2 = Car("Corvette", 2025, "blue", True)
car3 = Car("Charger", 2026, "yellow", True)
car1.drive()
# 你正在驾驶 red Mustang
car1.stop()
# 你停下了 red Mustang
car1.describe()
# 2024 red Mustang
46. 类变量 🎓
类变量 = 在类的所有实例之间共享
在构造函数之外定义
允许你在该类的所有对象之间共享数据
class Car:
wheels = 4 # 类变量
def __init__(self, model, year):
self.model = model # 实例变量
self.year = year # 实例变量
class Student:
class_year = 2024 # 类变量
def __init__(self, name, age):
self.name = name
self.age = age
student1 = Student("Spongebob", 30)
student2 = Student("Patrick", 35)
print(student1.name)
print(student1.age)
# Spongebob
# 30
print(student1.class_year)
print(student2.class_year)
print(Student.class_year)
# 2024
# 2024
# 2024
class Student:
class_year = 2024 # 类变量
num_students = 0 # 类变量
def __init__(self, name, age):
self.name = name
self.age = age
Student.num_students += 1
student1 = Student("Spongebob", 30)
student2 = Student("Patrick", 35)
student3 = Student("Squidward", 35)
student4 = Student("Sandy", 35)
print(Student.num_students)
# 4
print(f"我的 {Student.class_year} 届毕业班有 {Student.num_students} 名学生")
print(student1.name)
print(student2.name)
print(student3.name)
print(student4.name)
# 我的 2024 届毕业班有 4 名学生
# Spongebob
# Patrick
# Squidward
# Sandy
47. 继承 👨👦👦
继承 = 允许一个类从另一个类继承属性和方法
有助于代码的可重用性和扩展性
class Child(Parent)
class Sub(Super)
class Father:
height = 182
color = "pink"
class Son(Father):
pass
class Animal:
def __init__(self, name):
self.name = name
self.is_alive = True
def eat(self):
print(f"{self.name} 在吃东西")
def sleep(self):
print(f"{self.name} 在睡觉")
class Dog(Animal):
pass
class Cat(Animal):
pass
class Mouse(Animal):
pass
dog = Dog("Scooby")
cat = Cat("Garfield")
mouse = Mouse("Mickey")
print(dog.name)
print(dog.is_alive)
dog.eat()
dog.sleep()
# Scooby
# True
# Scooby 在吃东西
# Scooby 在睡觉
class Animal:
def __init__(self, name):
self.name = name
self.is_alive = True
def eat(self):
print(f"{self.name} 在吃东西")
def sleep(self):
print(f"{self.name} 在睡觉")
class Dog(Animal):
def speak(self):
print("汪汪！")
class Cat(Animal):
def speak(self):
print("喵喵！")
class Mouse(Animal):
def speak(self):
print("吱吱！")
dog = Dog("Scooby")
cat = Cat("Garfield")
mouse = Mouse("Mickey")
dog.speak()
# 汪汪！
48. 多重继承 🐟
多重继承 = 从多个父类继承
C(A, B)
多重继承 = 从一个继承自另一个父类的父类继承
C(B) <- B(A) <- A
class Prey:
pass
class Predator:
pass
class Rabbit:
pass
class Hawk:
pass
class Fish:
pass
class Prey:
def flee(self):
print("这只动物在逃跑")
class Predator:
def hunt(self):
print("这只动物在狩猎")
class Rabbit(Prey):
pass
class Hawk(Predator):
pass
class Fish(Prey, Predator):
pass
rabbit = Rabbit()
hawk = Hawk()
fish = Fish()
rabbit.flee()
# 这只动物在逃跑
rabbit.hunt()
# AttributeError: 'Rabbit' 对象没有 'hunt' 属性
hawk.hunt()
# 这只动物在狩猎
hawk.flee()
# AttributeError: 'Hawk' 对象没有 'flee' 属性
fish.flee()
# 这只动物在逃跑
fish.hunt()
# 这只动物在狩猎
class Animal:
def __init__(self, name):
self.name = name
def eat(self):
print(f"{self.name} 在吃东西")
def sleep(self):
print(f"{self.name} 在睡觉")
class Prey(Animal):
def flee(self):
print(f"{self.name} 在逃跑")
class Predator(Animal):
def hunt(self):
print(f"{self.name} 在狩猎")
class Rabbit(Prey):
pass
class Hawk(Predator):
pass
class Fish(Prey, Predator):
pass
rabbit = Rabbit("Bugs")
hawk = Hawk("Tony")
fish = Fish("Nemo")
rabbit.eat()
# Bugs 在吃东西
rabbit.sleep()
# Bugs 在睡觉
rabbit.flee()
# Bugs 在逃跑
hawk.flee()
# AttributeError: 'Hawk' 对象没有 'flee' 属性
hawk.eat()
# Tony 在吃东西
hawk.hunt()
# Tony 在狩猎
fish.eat()
fish.sleep()
fish.flee()
fish.hunt()
# Nemo 在吃东西
# Nemo 在睡觉
# Nemo 在逃跑
# Nemo 在狩猎
49. super() 🔴
super() = 在子类中用于调用父类（超类）的方法的函数。
允许扩展继承方法的功能。
class Super: # 👨🏻
pass
class Sub(Super): # 👶🏻
pass
class super
class super(type, object_or_type=None)
返回一个代理对象，将方法调用委托给指定类型的父类或同级类。这对于访问在子类中被覆盖的继承方法非常有用。
object_or_type 参数决定方法解析顺序的搜索范围。搜索从 type 之后的类开始。
class Circle:
def __init__(self, color, is_filled, radius):
self.color = color
self.is_filled = is_filled
self.radius = radius
class Square:
def __init__(self, color, is_filled, width):
self.color = color
self.is_filled = is_filled
self.width = width
class Triangle:
def __init__(self, color, is_filled, width, height):
self.color = color
self.is_filled = is_filled
self.width = width
self.height = height
class Shape:
def __init__(self, color, is_filled):
self.color = color
self.is_filled = is_filled
class Circle(Shape):
def __init__(self, color, is_filled, radius):
super().__init__(color, is_filled)
self.radius = radius
class Square(Shape):
def __init__(self, color, is_filled, width):
super().__init__(color, is_filled)
self.width = width
class Triangle(Shape):
def __init__(self, color, is_filled, width, height):
super().__init__(color, is_filled)
self.width = width
self.height = height
circle = Circle(color="red", is_filled=True, radius=5)
square = Square(color="blue", is_filled=False, width=6)
triangle = Triangle(color="yellow", is_filled=True, width=7, height=8)
print(circle.color)
print(circle.is_filled)
print(f"{circle.radius}cm")
# 红色
# True
# 5cm
print(square.color)
print(square.is_filled)
print(f"{square.width}cm")
# 蓝色
# False
# 6cm
print(triangle.color)
print(triangle.is_filled)
print(f"{triangle.width}cm")
print(f"{triangle.height}cm")
# 黄色
# True
# 7cm
# 8cm
class Shape:
def __init__(self, color, is_filled):
self.color = color
self.is_filled = is_filled
def describe(self):
print(f"它是 {self.color} 并且 {'填充' if self.is_filled else '未填充'}")
class Circle(Shape):
def __init__(self, color, is_filled, radius):
super().__init__(color, is_filled)
self.radius = radius
class Square(Shape):
def __init__(self, color, is_filled, width):
super().__init__(color, is_filled)
self.width = width
class Triangle(Shape):
def __init__(self, color, is_filled, width, height):
super().__init__(color, is_filled)
self.width = width
self.height = height
circle = Circle(color="red", is_filled=True, radius=5)
square = Square(color="blue", is_filled=False, width=6)
triangle = Triangle(color="yellow", is_filled=True, width=7, height=8)
circle.describe()
# 它是红色并且填充
square.describe()
# 它是蓝色并且未填充
triangle.describe()
# 它是黄色并且填充
class Shape:
def __init__(self, color, is_filled):
self.color = color
self.is_filled = is_filled
def describe(self):
print(f"它是 {self.color} 并且 {'填充' if self.is_filled else '未填充'}")
class Circle(Shape):
def __init__(self, color, is_filled, radius):
super().__init__(color, is_filled)
self.radius = radius
def describe(self):
super().describe()
print(f"它是一个圆，面积为 {3.14 * self.radius * self.radius}cm^2")
class Square(Shape):
def __init__(self, color, is_filled, width):
super().__init__(color, is_filled)
self.width = width
def describe(self):
super().describe()
print(f"它是一个正方形，面积为 {self.width * self.width}cm^2")
class Triangle(Shape):
def __init__(self, color, is_filled, width, height):
super().__init__(color, is_filled)
self.width = width
self.height = height
def describe(self):
super().describe()
print(f"它是一个三角形，面积为 {self.width * self.height / 2}cm^2")
circle = Circle(color="red", is_filled=True, radius=5)
square = Square(color="blue", is_filled=False, width=6)
triangle = Triangle(color="yellow", is_filled=True, width=7, height=8)
circle.describe()
# 它是红色并且填充
# 它是一个圆，面积为 78.5cm^2
square.describe()
# 它是蓝色并且未填充
# 它是一个正方形，面积为 36cm^2
triangle.describe()
# 它是黄色并且填充
# 它是一个三角形，面积为 28.0cm^2
50. 多态 🎭
多态 (Polymorphism) = 希腊语，意为“具有多种形态或面貌”
Poly = 多种
Morphe = 形态
实现多态的两种方式
1. 继承 = 一个对象可以被视为与其父类相同的类型
2. “鸭子类型” = 对象必须具有必要的属性/方法
class Shape:
pass
class Circle(Shape):
pass
class Square(Shape):
pass
class Triangle(Shape):
pass
circle = Circle()
square = Square()
triangle = Triangle()
shapes = [Circle(), Square(), Triangle()]
from abc import ABC, abstractmethod
class Shape(ABC):
@abstractmethod
def area(self):
pass
class Circle(Shape):
def __init__(self, radius):
self.radius = radius
def area(self):
return 3.14 * self.radius ** 2
class Square(Shape):
def __init__(self, side):
self.side = side
def area(self):
return self.side ** 2
class Triangle(Shape):
def __init__(self, base, height):
self.base = base
self.height = height
def area(self):
return self.base * self.height * 0.5
shapes = [Circle(4), Square(5), Triangle(6, 7)]
for shape in shapes:
print(f"{shape.area()}cm²")
# 50.24cm²
# 25cm²
# 21.0cm²
(如何添加上标 ²)：
Windows：Alt + 0178
Mac：Control + Command + Space
from abc import ABC, abstractmethod
class Shape(ABC):
@abstractmethod
def area(self):
pass
class Circle(Shape):
def __init__(self, radius):
self.radius = radius
def area(self):
return 3.14 * self.radius ** 2
class Square(Shape):
def __init__(self, side):
self.side = side
def area(self):
return self.side ** 2
class Triangle(Shape):
def __init__(self, base, height):
self.base = base
self.height = height
def area(self):
return self.base * self.height * 0.5
class Pizza:
def __init__(self, topping, radius):
self.topping = topping
self.radius = radius
shapes = [Circle(4), Square(5), Triangle(6, 7), Pizza("pepperoni", 15)]
for shape in shapes:
print(f"{shape.area()}cm²")
# AttributeError: 'Pizza' object has no attribute 'area'
# 50.24cm²
# 25cm²
# 21.0cm²
from abc import ABC, abstractmethod
class Shape(ABC):
@abstractmethod
def area(self):
pass
class Circle(Shape):
def __init__(self, radius):
self.radius = radius
def area(self):
return 3.14 * self.radius ** 2
class Square(Shape):
def __init__(self, side):
self.side = side
def area(self):
return self.side ** 2
class Triangle(Shape):
def __init__(self, base, height):
self.base = base
self.height = height
def area(self):
return self.base * self.height * 0.5
class Pizza(Circle):
def __init__(self, topping, radius):
super().__init__(radius)
self.topping = topping
shapes = [Circle(4), Square(5), Triangle(6, 7), Pizza("pepperoni", 15)]
for shape in shapes:
print(f"{shape.area()}cm²")
# 50.24cm²
# 25cm²
# 21.0cm²
# 706.5cm²
51. 鸭子类型 🦆
“鸭子类型” = 实现多态的另一种方式，不依赖继承
对象必须具备必要的最小属性/方法
“如果它看起来像鸭子，叫起来像鸭子，那它就是鸭子。”
class Animal:
alive = True
class Dog(Animal):
def speak(self):
print("汪！")
class Cat(Animal):
def speak(self):
print("喵！")
class Car():
def horn(self):
print("嘟！")
animals = [Dog(), Cat(), Car()]
for animal in animals:
animal.speak()
# AttributeError: 'Car' 对象没有 'speak' 属性
# 汪！
# 喵！
class Animal:
alive = True
class Dog(Animal):
def speak(self):
print("汪！")
class Cat(Animal):
def speak(self):
print("喵！")
class Car():
def speak(self):
print("嘟！")
animals = [Dog(), Cat(), Car()]
for animal in animals:
animal.speak()
print(animal.alive)
# AttributeError: 'Car' 对象没有 'alive' 属性
# 汪！
# True
# 喵！
# True
# 嘟！
class Animal:
alive = True
class Dog(Animal):
def speak(self):
print("汪！")
class Cat(Animal):
def speak(self):
print("喵！")
class Car():
alive = False
def speak(self):
print("嘟！")
animals = [Dog(), Cat(), Car()]
for animal in animals:
animal.speak()
print(animal.alive)
# 汪！
# True
# 喵！
# True
# 嘟！
# False
52. 静态方法 ⚡
静态方法 = 属于类而不是该类实例（对象）的方法
通常用于通用工具函数
实例方法 = 最适合对类实例（对象）进行操作
# 实例方法
def get_info(self):
return f"{self.name} = {self.position}"
静态方法 = 最适合不需要访问类数据的工具函数
@staticmethod
def km_to_miles(kilometers):
return kilometers * 0.621371
class Employee:
def __init__(self, name, position):
self.name = name
self.position = position
def get_info(self):
return f"{self.name} = {self.position}"
@staticmethod
def is_valid_position(position):
valid_positions = ["经理", "收银员", "厨师", "清洁工"]
return position in valid_positions
print(Employee.is_valid_position("厨师"))
# True
print(Employee.is_valid_position("火箭科学家"))
# False
class Employee:
def __init__(self, name, position):
self.name = name
self.position = position
def get_info(self):
return f"{self.name} = {self.position}"
@staticmethod
def is_valid_position(position):
valid_positions = ["经理", "收银员", "厨师", "清洁工"]
return position in valid_positions
employee1 = Employee("尤金", "经理")
employee2 = Employee("鱿鱼哥", "收银员")
employee3 = Employee("海绵宝宝", "厨师")
print(Employee.is_valid_position("火箭科学家"))
# False
print(employee1.get_info())
print(employee2.get_info())
print(employee3.get_info())
# 尤金 = 经理
# 鱿鱼哥 = 收银员
# 海绵宝宝 = 厨师
53. 类方法 🏫
类方法：允许对类本身进行操作
以 cls 作为第一个参数，表示类本身。
实例方法：最适合对类实例（对象）的操作
静态方法：最适合无需访问类数据的工具函数
类方法：最适合类级别的数据或需要访问类本身的操作
class Student:
count = 0
def __init__(self, name, gpa):
self.name = name
self.gpa = gpa
Student.count += 1
# 实例方法
def get_info(self):
return f"{self.name} {self.gpa}"
@classmethod
def get_count(cls):
return f"学生总数：{cls.count}"
print(Student.get_count())
# 学生总数：0
class Student:
count = 0
def __init__(self, name, gpa):
self.name = name
self.gpa = gpa
Student.count += 1
# 实例方法
def get_info(self):
return f"{self.name} {self.gpa}"
@classmethod
def get_count(cls):
return f"学生总数：{cls.count}"
student1 = Student("Spongebob", 3.2)
student2 = Student("Patrick", 2.0)
student3 = Student("Sandy", 4.0)
print(Student.get_count())
# 学生总数：3
class Student:
count = 0
total_gpa = 0
def __init__(self, name, gpa):
self.name = name
self.gpa = gpa
Student.count += 1
Student.total_gpa += gpa # 修正：累加 gpa
# 实例方法
def get_info(self):
return f"{self.name} {self.gpa}"
@classmethod
def get_count(cls):
return f"学生总数：{cls.count}"
@classmethod
def get_average_gpa(cls):
if cls.count == 0:
return 0
else:
return f"平均 GPA: {cls.total_gpa / cls.count:.2f}"
student1 = Student("Spongebob", 3.2)
student2 = Student("Patrick", 2.0)
student3 = Student("Sandy", 4.0)
print(Student.get_count())
# 学生总数：3
print(Student.get_average_gpa())
# 平均 GPA: 3.07
54. 魔法方法 🌟
魔法方法 = 双下划线方法（Dunder methods），如 __init__、__str__、__eq__
它们会被 Python 的许多内置操作自动调用。
魔法方法允许开发者定义或自定义对象的行为。
class Student:
def __init__(self, name, gpa):
self.name = name
self.gpa = gpa
def __str__(self):
return f"姓名: {self.name} 平均绩点: {self.gpa}"
def __eq__(self, other):
return self.name == other.name
def __gt__(self, other):
return self.gpa > other.gpa
student1 = Student("Spongebob", 3.2)
student2 = Student("Patrick", 2.0)
print(student1)
print(student1 == student2)
print(student1 > student2)
# 姓名: Spongebob 平均绩点: 3.2
# False
# True
class Book:
def __init__(self, title, author, num_pages):
self.title = title
self.author = author
self.num_pages = num_pages
book1 = Book("霍比特人", "J.R.R. Tolkien", 310)
book2 = Book("哈利·波特与魔法石", "J.K. Rowling", 223)
book3 = Book("狮子、女巫与魔衣橱", "C.S. Lewis", 172)
print(book1)
# <__main__.Book object at 0x000001E78F76EE50>
class Book:
def __init__(self, title, author, num_pages):
self.title = title
self.author = author
self.num_pages = num_pages
def __str__(self):
return f"《{self.title}》 作者: {self.author}"
book1 = Book("霍比特人", "J.R.R. Tolkien", 310)
book2 = Book("哈利·波特与魔法石", "J.K. Rowling", 223)
book3 = Book("狮子、女巫与魔衣橱", "C.S. Lewis", 172)
book4 = Book("狮子、女巫与魔衣橱", "C.S. Lewis", 172)
print(book1)
# 《霍比特人》 作者: J.R.R. Tolkien
print(book3 == book4)
# False
class Book:
def __init__(self, title, author, num_pages):
self.title = title
self.author = author
self.num_pages = num_pages
def __str__(self):
return f"《{self.title}》 作者: {self.author}"
def __eq__(self, other):
return self.title == other.title and self.author == other.author
book1 = Book("霍比特人", "J.R.R. Tolkien", 310)
book2 = Book("哈利·波特与魔法石", "J.K. Rowling", 223)
book3 = Book("狮子、女巫与魔衣橱", "C.S. Lewis", 172)
book4 = Book("狮子、女巫与魔衣橱", "C.S. Lewis", 17222)
print(book1)
# 《霍比特人》 作者: J.R.R. Tolkien
print(book3 == book4)
# True
print(book2 < book3)
# TypeError: '<' not supported between instances of 'Book' and 'Book'
class Book:
def __init__(self, title, author, num_pages):
self.title = title
self.author = author
self.num_pages = num_pages
def __str__(self):
return f"《{self.title}》 作者: {self.author}"
def __eq__(self, other):
return self.title == other.title and self.author == other.author
def __lt__(self, other):
return self.num_pages < other.num_pages
def __gt__(self, other):
return self.num_pages > other.num_pages
book1 = Book("霍比特人", "J.R.R. Tolkien", 310)
book2 = Book("哈利·波特与魔法石", "J.K. Rowling", 223)
book3 = Book("狮子、女巫与魔衣橱", "C.S. Lewis", 172)
book4 = Book("狮子、女巫与魔衣橱", "C.S. Lewis", 17222)
print(book2 < book3)
# False
print(book2 > book3)
# True
print(book2 + book3)
# TypeError: unsupported operand type(s) for +: 'Book' and 'Book'
class Book:
def __init__(self, title, author, num_pages):
self.title = title
self.author = author
self.num_pages = num_pages
def __str__(self):
return f"《{self.title}》 作者: {self.author}"
def __eq__(self, other):
return self.title == other.title and self.author == other.author
def __lt__(self, other):
return self.num_pages < other.num_pages
def __gt__(self, other):
return self.num_pages > other.num_pages
def __add__(self, other):
return f"{self.num_pages + other.num_pages} 页"
book1 = Book("霍比特人", "J.R.R. Tolkien", 310)
book2 = Book("哈利·波特与魔法石", "J.K. Rowling", 223)
book3 = Book("狮子、女巫与魔衣橱", "C.S. Lewis", 172)
book4 = Book("狮子、女巫与魔衣橱", "C.S. Lewis", 17222)
print(book2 + book3)
# 395 页
print("狮子" in book3)
# TypeError: argument of type 'Book' is not iterable
class Book:
def __init__(self, title, author, num_pages):
self.title = title
self.author = author
self.num_pages = num_pages
def __str__(self):
return f"《{self.title}》 作者: {self.author}"
def __eq__(self, other):
return self.title == other.title and self.author == other.author
def __lt__(self, other):
return self.num_pages < other.num_pages
def __gt__(self, other):
return self.num_pages > other.num_pages
def __add__(self, other):
return f"{self.num_pages + other.num_pages} 页"
def __contains__(self, keyword):
return keyword in self.title or keyword in self.author
book1 = Book("霍比特人", "J.R.R. Tolkien", 310)
book2 = Book("哈利·波特与魔法石", "J.K. Rowling", 223)
book3 = Book("狮子、女巫与魔衣橱", "C.S. Lewis", 172)
print("狮子" in book3)
# True
print("狮子" in book1)
# False
print("Rowling" in book2)
# True
print("Rowling" in book3)
# False
print(book1['title'])
# TypeError: 'Book' object is not subscriptable
class Book:
def __init__(self, title, author, num_pages):
self.title = title
self.author = author
self.num_pages = num_pages
def __str__(self):
return f"《{self.title}》 作者: {self.author}"
def __eq__(self, other):
return self.title == other.title and self.author == other.author
def __lt__(self, other):
return self.num_pages < other.num_pages
def __gt__(self, other):
return self.num_pages > other.num_pages
def __add__(self, other):
return f"{self.num_pages + other.num_pages} 页"
def __contains__(self, keyword):
return keyword in self.title or keyword in self.author
def __getitem__(self, key):
if key == "title":
return self.title
book1 = Book("霍比特人", "J.R.R. Tolkien", 310)
book2 = Book("哈利·波特与魔法石", "J.K. Rowling", 223)
book3 = Book("狮子、女巫与魔衣橱", "C.S. Lewis", 172)
print(book1['title'])
# 霍比特人
print(book2['title'])
# 哈利·波特与魔法石
print(book3['title'])
# 狮子、女巫与魔衣橱
print(book3['author'])
# None
class Book:
def __init__(self, title, author, num_pages):
self.title = title
self.author = author
self.num_pages = num_pages
def __str__(self):
return f"《{self.title}》 作者: {self.author}"
def __eq__(self, other):
return self.title == other.title and self.author == other.author
def __lt__(self, other):
return self.num_pages < other.num_pages
def __gt__(self, other):
return self.num_pages > other.num_pages
def __add__(self, other):
return f"{self.num_pages + other.num_pages} 页"
def __contains__(self, keyword):
return keyword in self.title or keyword in self.author
def __getitem__(self, key):
if key == "title":
return self.title
elif key == "author":
return self.author
book1 = Book("霍比特人", "J.R.R. Tolkien", 310)
book2 = Book("哈利·波特与魔法石", "J.K. Rowling", 223)
book3 = Book("狮子、女巫与魔衣橱", "C.S. Lewis", 172)
print(book3['author'])
# C.S. Lewis
print(book2['author'])
# J.K. Rowling
print(book1['author'])
# J.R.R. Tolkien
print(book1['num_pages'])
# None
class Book:
def __init__(self, title, author, num_pages):
self.title = title
self.author = author
self.num_pages = num_pages
def __str__(self):
return f"《{self.title}》 作者: {self.author}"
def __eq__(self, other):
return self.title == other.title and self.author == other.author
def __lt__(self, other):
return self.num_pages < other.num_pages
def __gt__(self, other):
return self.num_pages > other.num_pages
def __add__(self, other):
return f"{self.num_pages + other.num_pages} 页"
def __contains__(self, keyword):
return keyword in self.title or keyword in self.author
def __getitem__(self, key):
if key == "title":
return self.title
elif key == "author":
return self.author
elif key == "num_pages":
return self.num_pages
else:
return f"键 '{key}' 未找到"
book1 = Book("霍比特人", "J.R.R. Tolkien", 310)
book2 = Book("哈利·波特与魔法石", "J.K. Rowling", 223)
book3 = Book("狮子、女巫与魔衣橱", "C.S. Lewis", 172)
print(book1['num_pages'])
# 310
print(book2['num_pages'])
# 223
print(book3['num_pages'])
# 172
print(book3['audio'])
# 键 'audio' 未找到
55. @property ⚙️
@property 是一个装饰器，用于将方法定义为属性（可以像访问属性一样访问方法）。
优势：在读取、写入或删除属性时可以添加额外的逻辑。
提供 getter、setter 和 deleter 方法。
class Rectangle:
def __init__(self, width, height):
self.width = width
self.height = height
rectangle = Rectangle(3, 4)
print(rectangle.width)
print(rectangle.height)
# 3
# 4
class Rectangle:
def __init__(self, width, height):
self._width = width
self._height = height
@property
def width(self):
pass
@property
def height(self):
pass
rectangle = Rectangle(3, 4)
print(rectangle.width)
print(rectangle.height)
# 3
# 4
class Rectangle:
def __init__(self, width, height):
self._width = width
self._height = height
@property
def width(self):
return f"{self._width:.1f}cm"
@property
def height(self):
return f"{self._height:.1f}cm"
rectangle = Rectangle(3, 4)
print(rectangle.width)
print(rectangle.height)
# 3.0cm
# 4.0cm
print(rectangle._width)
print(rectangle._height)
# 3
# 4
class Rectangle:
def __init__(self, width, height):
self._width = width
self._height = height
@property
def width(self):
return f"{self._width:.1f}cm"
@property
def height(self):
return f"{self._height:.1f}cm"
@width.setter
def width(self, new_width):
if new_width > 0:
self._width = new_width
else:
print("宽度必须大于零")
@height.setter
def height(self, new_height):
if new_height > 0:
self._height = new_height
else:
print("高度必须大于零")
rectangle = Rectangle(3, 4)
rectangle.width = 0
rectangle.height = -1
print(rectangle.width)
print(rectangle.height)
# 宽度必须大于零
# 高度必须大于零
# 3.0cm
# 4.0cm
class Rectangle:
def __init__(self, width, height):
self._width = width
self._height = height
@property
def width(self):
return f"{self._width:.1f}cm"
@property
def height(self):
return f"{self._height:.1f}cm"
@width.setter
def width(self, new_width):
if new_width > 0:
self._width = new_width
else:
print("宽度必须大于零")
@height.setter
def height(self, new_height):
if new_height > 0:
self._height = new_height
else:
print("高度必须大于零")
rectangle = Rectangle(3, 4)
rectangle.width = 5
rectangle.height = 6
print(rectangle.width)
print(rectangle.height)
# 5.0cm
# 6.0cm
class Rectangle:
def __init__(self, width, height):
self._width = width
self._height = height
@property
def width(self):
return f"{self._width:.1f}cm"
@property
def height(self):
return f"{self._height:.1f}cm"
@width.setter
def width(self, new_width):
if new_width > 0:
self._width = new_width
else:
print("宽度必须大于零")
@height.setter
def height(self, new_height):
if new_height > 0:
self._height = new_height
else:
print("高度必须大于零")
@width.deleter
def width(self):
del self._width
print("宽度已被删除")
@height.deleter
def height(self):
del self._height
print("高度已被删除")
rectangle = Rectangle(3, 4)
rectangle.width = 5
rectangle.height = 6
del rectangle.width
del rectangle.height
# 宽度已被删除
# 高度已被删除
56. 装饰器 🎊
装饰器 = 一个扩展另一个函数行为的函数
无需修改原函数
将原函数作为参数传递给装饰器
@add_sprinkles
get_ice_cream(“vanilla”)
def get_ice_cream():
print("这是你的冰淇淋 🍨")
get_ice_cream()
# 这是你的冰淇淋 🍨
def add_sprinkles(func):
def wrapper():
func() # print("这是你的冰淇淋 🍨")
return wrapper
@add_sprinkles
def get_ice_cream():
print("这是你的冰淇淋 🍨")
get_ice_cream()
# 这是你的冰淇淋 🍨
def add_sprinkles(func):
def wrapper():
print("*你添加了彩糖 🎊*")
func()
return wrapper
@add_sprinkles
def get_ice_cream():
print("这是你的冰淇淋 🍨")
get_ice_cream()
# *你添加了彩糖 🎊*
# 这是你的冰淇淋 🍨
def add_sprinkles(func):
print("*你添加了彩糖 🎊*")
func()
@add_sprinkles
def get_ice_cream():
print("这是你的冰淇淋 🍨")
# *你添加了彩糖 🎊*
# 这是你的冰淇淋 🍨
def add_sprinkles(func):
def wrapper():
print("*你添加了彩糖 🎊*")
func()
return wrapper
def add_fudge(func):
def wrapper():
print("*你添加了巧克力酱 🍫*")
func()
return wrapper
@add_sprinkles
@add_fudge
def get_ice_cream():
print("这是你的冰淇淋 🍨")
get_ice_cream()
# *你添加了彩糖 🎊*
# *你添加了巧克力酱 🍫*
# 这是你的冰淇淋 🍨
def add_sprinkles(func):
def wrapper():
print("*你添加了彩糖 🎊*")
func()
return wrapper
def add_fudge(func):
def wrapper():
print("*你添加了巧克力酱 🍫*")
func()
return wrapper
@add_sprinkles
@add_fudge
def get_ice_cream(flavo):
print(f"这是你的{flavo}冰淇淋 🍨")
get_ice_cream("vanilla")
# TypeError: add_sprinkles.<locals>.wrapper() 接受 0 个位置参数，但给定了 1 个
def add_sprinkles(func):
def wrapper(*args, **kwargs):
print("*你添加了彩糖 🎊*")
func(*args, **kwargs)
return wrapper
def add_fudge(func):
def wrapper(*args, **kwargs):
print("*你添加了巧克力酱 🍫*")
func(*args, **kwargs)
return wrapper
@add_sprinkles
@add_fudge
def get_ice_cream(flavo):
print(f"这是你的{flavo}冰淇淋 🍨")
get_ice_cream("vanilla")
# *你添加了彩糖 🎊*
# *你添加了巧克力酱 🍫*
# 这是你的vanilla冰淇淋 🍨
57. 异常处理 🚦
异常 = 中断程序流程的事件
（ZeroDivisionError、TypeError、ValueError）
1. try, 2. except, 3. finally
1 / 0
# ZeroDivisionError: 除以零
1 + "1"
# TypeError: 对于 + 操作，'int' 和 'str' 类型不受支持
int("pizza")
# ValueError: 以 10 为基数的 int() 无效字面量：'pizza'
try:
# 尝试运行一些代码
except Exception:
# 处理异常
finally:
# 进行一些清理工作
number = int(input("请输入一个数字："))
print(1 / number)
# 输入一个数字：0
# ZeroDivisionError: 除以零
# 输入一个数字：pizza
# ValueError: 以 10 为基数的 int() 无效字面量：'pizza'
try:
number = int(input("请输入一个数字："))
print(1 / number)
except ZeroDivisionError:
print("你不能除以零，傻瓜！")
except ValueError:
print("请输入数字！")
# 输入一个数字：0
# 你不能除以零，傻瓜！
# 输入一个数字：pizza
# 请输入数字！
try:
number = int(input("请输入一个数字："))
print(1 / number)
except ZeroDivisionError:
print("你不能除以零，傻瓜！")
except ValueError:
print("请输入数字！")
except Exception: # 过于宽泛的异常条款
print("出错了！")
finally:
print("在这里进行一些清理工作")
# 输入一个数字：0
# 你不能除以零，傻瓜！
# 在这里进行一些清理工作
# 输入一个数字：1
# 1.0
# 在这里进行一些清理工作
异常类型有很多种，你可以随时查看 Python 官方文档 获取详细列表。这就是 Python 中的异常处理。
58. 文件检测 🕵️♂️
<!-- test.txt -->
喜欢披萨
# main.py
import os
file_path = "test.txt"
if os.path.exists(file_path):
print(f"位置 '{file_path}' 存在")
else:
print("该位置不存在")
# 输出：位置 'test.txt' 存在
# main.py
import os
file_path = "test.txt"
if os.path.exists(file_path):
print(f"位置 '{file_path}' 存在")
if os.path.isfile(file_path):
print("这是一个文件")
elif os.path.isdir(file_path):
print("这是一个目录")
else:
print("该位置不存在")
# 输出：
# 位置 'test.txt' 存在
# 这是一个文件
59. 写入文件 ✍
Python 写入文件（.txt、.json、.csv）
txt_data = "我喜欢披萨！"
file_path = "output.txt"
with open(file_path, "w") as file:
file.write(txt_data)
print(f"文本文件 '{file_path}' 已创建")
# 文本文件 'output.txt' 已创建
# <!-- output.txt -->
# 我喜欢披萨！
txt_data = "我喜欢披萨！"
file_path = "output.txt"
try:
with open(file_path, "x") as file:
file.write(txt_data)
print(f"文本文件 '{file_path}' 已创建")
except FileExistsError:
print("该文件已存在！")
# 该文件已存在！
<!-- output.txt -->
我喜欢披萨！
txt_data = "我喜欢披萨！"
file_path = "output.txt"
try:
with open(file_path, "a") as file:
file.write(txt_data)
print(f"文本文件 '{file_path}' 已创建")
except FileExistsError:
print("该文件已存在！")
# 文本文件 'output.txt' 已创建
# <!-- output.txt -->
# 我喜欢披萨！我喜欢披萨！
<!-- output.txt -->
我喜欢披萨！我喜欢披萨！
txt_data = "我喜欢披萨！"
file_path = "output.txt"
try:
with open(file_path, "a") as file:
file.write(txt_data)
print(f"文本文件 '{file_path}' 已创建")
except FileExistsError:
print("该文件已存在！")
# 文本文件 'output.txt' 已创建
# <!-- output.txt -->
# 我喜欢披萨！
<!-- output.txt -->
我喜欢披萨！
txt_data = "我喜欢披萨！"
file_path = "output.txt"
try:
with open(file_path, "a") as file:
file.write("\n" + txt_data)
print(f"文本文件 '{file_path}' 已创建")
except FileExistsError:
print("该文件已存在！")
# 文本文件 'output.txt' 已创建
# <!-- output.txt -->
# 我喜欢披萨！
# 我喜欢披萨！
employees = ["尤金", "鱿鱼哥", "海绵宝宝", "派大星"]
file_path = "output.txt"
try:
with open(file_path, "w") as file:
file.write(employees)
print(f"文本文件 '{file_path}' 已创建")
except FileExistsError:
print("该文件已存在！")
# TypeError: write() 参数必须是字符串，而不是列表
employees = ["尤金", "鱿鱼哥", "海绵宝宝", "派大星"]
file_path = "output.txt"
try:
with open(file_path, "w") as file:
for employee in employees:
file.write(employee)
print(f"文本文件 '{file_path}' 已创建")
except FileExistsError:
print("该文件已存在！")
# 文本文件 'output.txt' 已创建
# <!-- output.txt -->
# 尤金鱿鱼哥海绵宝宝派大星
employees = ["尤金", "鱿鱼哥", "海绵宝宝", "派大星"]
file_path = "output.txt"
try:
with open(file_path, "w") as file:
for employee in employees:
file.write(employee + "\n")
print(f"文本文件 '{file_path}' 已创建")
except FileExistsError:
print("该文件已存在！")
# 文本文件 'output.txt' 已创建
# <!-- output.txt -->
# 尤金
# 鱿鱼哥
# 海绵宝宝
# 派大星
import json
employee = {
"name": "海绵宝宝",
"age": 30,
"job": "厨师"
}
file_path = "output.json"
try:
with open(file_path, "w") as file:
json.dump(employee, file)
print(f"JSON 文件 '{file_path}' 已创建")
except FileExistsError:
print("该文件已存在！")
# JSON 文件 'output.json' 已创建
# <!-- output.json -->
# {"name": "海绵宝宝", "age": 30, "job": "厨师"}
import json
employee = {
"name": "海绵宝宝",
"age": 30,
"job": "厨师"
}
file_path = "output.json"
try:
with open(file_path, "w") as file:
json.dump(employee, file, indent=4)
print(f"JSON 文件 '{file_path}' 已创建")
except FileExistsError:
print("该文件已存在！")
# JSON 文件 'output.json' 已创建
# <!-- output.json -->
# {
# "name": "海绵宝宝",
# "age": 30,
# "job": "厨师"
# }
import json
import csv
employees = [["姓名", "年龄", "职业"],
["海绵宝宝", 30, "厨师"],
["派大星", 37, "无业"],
["珊迪", 27, "科学家"]]
file_path = "output.csv"
try:
with open(file_path, "手法
with open(file_path, "w") as file:
writer = csv.writer(file)
for row in employees:
writer.writerow(row)
print(f"CSV 文件 '{file_path}' 已创建")
except FileExistsError:
print("该文件已存在！")
# CSV 文件 'output.csv' 已创建
# <!-- output.csv -->
# 姓名,年龄,职业
#
# 海绵宝宝,30,厨师
#
# 派大星,37,无业
#
# 珊迪,27,科学家
import json
import csv
employees = [["姓名", "年龄", "职业"],
["海绵宝宝", 30, "厨师"],
["派大星", 37, "无业"],
["珊迪", 27, "科学家"]]
file_path = "output.csv"
try:
with open(file_path, "w", newline="") as file:
writer = csv.writer(file)
for row in employees:
writer.writerow(row)
print(f"CSV 文件 '{file_path}' 已创建")
except FileExistsError:
print("该文件已存在！")
# CSV 文件 'output.csv' 已创建
# <!-- output.csv -->
# 姓名,年龄,职业
# 海绵宝宝,30,厨师
# 派大星,37,无业
# 珊迪,27,科学家
60. 读取文件 🔍
Python 读取文件（.txt、.json、csv）
<!-- input.txt -->
我喜欢披萨！
它真的很好吃！
// input.json
{
"name": "海绵宝宝",
"age": 30,
"job": "厨师"
}
<!-- input.csv -->
姓名,年龄,职业
海绵宝宝,30,厨师
派大星,37,无业
珊迪,27,科学家
file_path = "input.txt"
with open(file_path, "r") as file:
content = file.read()
print(content)
# 我喜欢披萨！
# 它真的很好吃！
with 语句用于封装一个代码块的执行，通过上下文管理器定义的方法（参见 With 语句上下文管理器 部分）。这可以将常见的 try...except...finally 使用模式封装起来，便于重用。
import json
file_path = "input.json"
try:
with open(file_path, "r") as file:
content = json.load(file)
print(content)
print(content["name"])
except FileNotFoundError:
print("未找到该文件")
except PermissionError:
print("您没有权限读取该文件")
# {"name": "海绵宝宝", "age": 30, "job": "厨师"}
# 海绵宝宝
import csv
file_path = "input.csv"
try:
with open(file_path, "r") as file:
content = csv.reader(file)
print(content)
except FileNotFoundError:
print("未找到该文件")
except PermissionError:
print("您没有权限读取该文件")
# <_csv.reader object at 0x0000017D81C4EAA0>
import csv
file_path = "input.csv"
try:
with open(file_path, "r") as file:
content = csv.reader(file)
for line in content:
print(line)
except FileNotFoundError:
print("未找到该文件")
except PermissionError:
print("您没有权限读取该文件")
# ['姓名', '年龄', '职业']
# ['海绵宝宝', '30', '厨师']
# ['派大星', '37', '无业']
# ['珊迪', '27', '科学家']
import csv
file_path = "input.csv"
try:
with open(file_path, "r") as file:
content = csv.reader(file)
for line in content:
print(line[0])
except FileNotFoundError:
print("未找到该文件")
except PermissionError:
print("您没有权限读取该文件")
# 姓名
# 海绵宝宝
# 派大星
# 珊迪
61. 日期与时间 📅
import datetime
date = datetime.date(2025, 1, 2)
print(date)
# 2025-01-02
today = datetime.date.today()
print(today)
# 2025-05-02
time = datetime.time(12, 30, 0)
print(time)
# 12:30:00
now = datetime.datetime.now()
print(now)
# 2025-05-02 09:41:55.409676
now = now.strftime("%H %M %S")
print(now)
# 09 41 55
now = now.strftime("%H:%M:%S")
print(now)
# 09:41:55
now = now.strftime("%H:%M:%S %m-%d-%Y")
print(now)
# 09:41:55 05-02-2025
| 指令 | 含义 | 示例 | 备注 |
|---|---|---|---|
%a |
工作日，基于本地语言的缩写名称。 | Sun, Mon, …, Sat (en_US); So, Mo, …, Sa (de_DE) |
(1) |
%A |
工作日，基于本地语言的完整名称。 | Sunday, Monday, …, Saturday (en_US); Sonntag, Montag, …, Samstag (de_DE) |
(1) |
%w |
工作日，十进制数字表示，0为周日，6为周六。 | 0, 1, …, 6 | |
%d |
月份中的日期，零填充的十进制数字。 | 01, 02, …, 31 | (9) |
%b |
月份，基于本地语言的缩写名称。 | Jan, Feb, …, Dec (en_US); Jan, Feb, …, Dez (de_DE) |
(1) |
%B |
月份，基于本地语言的完整名称。 | January, February, …, December (en_US); Januar, Februar, …, Dezember (de_DE) |
(1) |
%m |
月份，零填充的十进制数字。 | 01, 02, …, 12 | (9) |
%y |
不带世纪的年份，零填充的十进制数字。 | 00, 01, …, 99 | (9) |
%Y |
带世纪的年份，十进制数字。 | 0001, 0002, …, 2013, 2014, …, 9998, 9999 | (2) |
strftime 支持多种格式代码。你可以随时查阅 Python strftime 文档 获取完整的格式代码列表和详细说明。
import datetime
date = datetime.date(2025, 1, 2)
today = datetime.date.today()
time = datetime.time(12, 30, 0)
now = datetime.datetime.now()
now = now.strftime("%H:%M:%S %m-%d-%Y")
target_datetime = datetime.datetime(2030, 1, 2, 12, 12, 30, 1)
curren_datetime = datetime.datetime.now()
if target_datetime < curren_datetime:
print("目标日期已过去")
else:
print("目标日期尚未过去")
# 目标日期尚未过去
62. ⭐ 闹钟 ⏰
# Python 闹钟
import time
import datetime
import pygame # pip install pygame
def set_alarm(alarm_time): # 例如 "23:00:00"
pass
if __name__ == '__main__':
alarm_time = input("请输入闹钟时间 (HH:MM:SS): ")
set_alarm(alarm_time)
# Python 闹钟
import time
import datetime
import pygame
def set_alarm(alarm_time):
print(f"闹钟已设置为 {alarm_time}")
sound_file = "my_music.mp3"
if __name__ == '__main__':
alarm_time = input("请输入闹钟时间 (HH:MM:SS): ")
set_alarm(alarm_time)
# pygame 2.6.0 (SDL 2.28.4, Python 3.12.5)
# 来自 pygame 社区的问候。https://www.pygame.org/contribute.html
👆"此功能实现在 pygame 库的初始化文件中 (/.venv/Lib/site-packages/pygame/__init__.py 第338-342行)。"
# 请输入闹钟时间 (HH:MM:SS): 09:00:00
# 闹钟已设置为 09:00:00
# Python 闹钟
import time
import datetime
import pygame
def set_alarm(alarm_time):
print(f"闹钟已设置为 {alarm_time}")
sound_file = "my_music.mp3"
is_running = True
while is_running:
curren_datetime = datetime.datetime.now().strftime("%H:%M:%S")
print(curren_datetime)
is_running = False
if __name__ == '__main__':
alarm_time = input("请输入闹钟时间 (HH:MM:SS): ")
set_alarm(alarm_time)
# 请输入闹钟时间 (HH:MM:SS): 10:00:00
# 闹钟已设置为 10:00:00
# 09:42:16
# Python 闹钟
import time
import datetime
import pygame
def set_alarm(alarm_time):
print(f"闹钟已设置为 {alarm_time}")
sound_file = "my_music.mp3"
is_running = True
while is_running:
curren_datetime = datetime.datetime.now().strftime("%H:%M:%S")
print(curren_datetime)
time.sleep(1)
if __name__ == '__main__':
alarm_time = input("请输入闹钟时间 (HH:MM:SS): ")
set_alarm(alarm_time)
# 请输入闹钟时间 (HH:MM:SS): 10:00:00
# 闹钟已设置为 10:00:00
# 09:42:16
# 09:42:17
# 09:42:18
# ...
# Python 闹钟
import time
import datetime
import pygame
def set_alarm(alarm_time):
print(f"闹钟已设置为 {alarm_time}")
sound_file = "my_music.mp3"
is_running = True
while is_running:
curren_datetime = datetime.datetime.now().strftime("%H:%M:%S")
print(curren_datetime)
if curren_datetime == alarm_time:
print("起床啦！")
is_running = False
time.sleep(1)
if __name__ == '__main__':
alarm_time = input("请输入闹钟时间 (HH:MM:SS): ")
set_alarm(alarm_time)
# 请输入闹钟时间 (HH:MM:SS): 09:45:00
# 闹钟已设置为 09:45:00
# ...
# 09:44:58
# 09:44:59
# 09:45:00
# 起床啦！
# 进程以退出码 0 结束
# Python 闹钟
import time
import datetime
import pygame
def set_alarm(alarm_time):
print(f"闹钟已设置为 {alarm_time}")
sound_file = "my_music.mp3"
is_running = True
while is_running:
curren_datetime = datetime.datetime.now().strftime("%H:%M:%S")
print(curren_datetime)
if curren_datetime == alarm_time:
print("起床啦！")
pygame.mixer.init()
pygame.mixer.music.load(sound_file)
pygame.mixer.music.play()
is_running = False
time.sleep(1)
if __name__ == '__main__':
alarm_time = input("请输入闹钟时间 (HH:MM:SS): ")
set_alarm(alarm_time)
# 请输入闹钟时间 (HH:MM:SS): 09:45:00
# 闹钟已设置为 09:45:00
# ...
# 09:44:58
# 09:44:59
# 09:45:00
# 起床啦！
# 进程以退出码 0 结束
模块 pygame.mixer: 用于加载和播放声音的 pygame 模块
# pygame.mixer
def init(frequency: int = 44100,
size: int = -16,
channels: int = 2,
buffer: int = 512,
devicename: str | None = None,
allowedchanges: int = 5) -> None
# Python 闹钟
import time
import datetime
import pygame
def set_alarm(alarm_time):
print(f"闹钟已设置为 {alarm_time}")
sound_file = "my_music.mp3"
is_running = True
while is_running:
curren_datetime = datetime.datetime.now().strftime("%H:%M:%S")
print(curren_datetime)
if curren_datetime == alarm_time:
print("起床啦！")
pygame.mixer.init()
pygame.mixer.music.load(sound_file)
pygame.mixer.music.play()
while pygame.mixer.music.get_busy():
time.sleep(1)
is_running = False
time.sleep(1)
if __name__ == '__main__':
alarm_time = input("请输入闹钟时间 (HH:MM:SS): ")
set_alarm(alarm_time)
# 请输入闹钟时间 (HH:MM:SS): 09:45:00
# 闹钟已设置为 09:45:00
# ...
# 09:44:58
# 09:44:59
# 09:45:00
# 起床啦！
👆这就是如何用 Python 创建一个闹钟。
63. 多线程 🧵
多线程 = 用于同时执行多个任务（multithreading）
适用于I/O密集型任务，如读取文件或从API获取数据
threading.Thread(target=my_function)
import threading
import time
def walk_dog():
time.sleep(8)
print("你遛完狗了")
def take_out_trash():
time.sleep(2)
print("你倒完垃圾了")
def get_mail():
time.sleep(4)
print("你取完邮件了")
walk_dog()
take_out_trash()
get_mail()
# 你遛完狗了
# 你倒完垃圾了
# 你取完邮件了
import threading
import time
def walk_dog():
time.sleep(8)
print("你遛完狗了")
def take_out_trash():
time.sleep(2)
print("你倒完垃圾了")
def get_mail():
time.sleep(4)
print("你取完邮件了")
chore1 = threading.Thread(target=walk_dog)
chore1.start()
chore2 = threading.Thread(target=take_out_trash)
chore2.start()
chore3 = threading.Thread(target=get_mail)
chore3.start()
print("所有家务都完成了！")
# 所有家务都完成了！
# 你倒完垃圾了
# 你取完邮件了
# 你遛完狗了
import threading
import time
def walk_dog():
time.sleep(8)
print("你遛完狗了")
def take_out_trash():
time.sleep(2)
print("你倒完垃圾了")
def get_mail():
time.sleep(4)
print("你取完邮件了")
chore1 = threading.Thread(target=walk_dog)
chore1.start()
chore2 = threading.Thread(target=take_out_trash)
chore2.start()
chore3 = threading.Thread(target=get_mail)
chore3.start()
print("所有家务都完成了！")
chore1.join()
chore2.join()
chore3.join()
# 你倒完垃圾了
# 你取完邮件了
# 你遛完狗了
# 所有家务都完成了！
import threading
import time
def walk_dog(first):
time.sleep(8)
print(f"你遛完{first}了")
def take_out_trash():
time.sleep(2)
print("你倒完垃圾了")
def get_mail():
time.sleep(4)
print("你取完邮件了")
# 被解释为括号中的字符串
chore1 = threading.Thread(target=walk_dog, args=("Scooby",))
chore1.start()
chore2 = threading.Thread(target=take_out_trash)
chore2.start()
chore3 = threading.Thread(target=get_mail)
chore3.start()
print("所有家务都完成了！")
chore1.join()
chore2.join()
chore3.join()
# 你倒完垃圾了
# 你取完邮件了
# 你遛完Scooby了
# 所有家务都完成了！
import threading
import time
def walk_dog(first):
time.sleep(8)
print(f"你遛完{first}了")
def take_out_trash():
time.sleep(2)
print("你倒完垃圾了")
def get_mail():
time.sleep(4)
print("你取完邮件了")
# 被解释为括号中的字符串
chore1 = threading.Thread(target=walk_dog, args=("Scooby"))
chore1.start()
chore2 = threading.Thread(target=take_out_trash)
chore2.start()
chore3 = threading.Thread(target=get_mail)
chore3.start()
print("所有家务都完成了！")
chore1.join()
chore2.join()
chore3.join()
# TypeError: walk_dog() 接受1个位置参数，但给出了6个
# 你倒完垃圾了
# 你取完邮件了
# 你遛完Scooby了
# 所有家务都完成了！
import threading
import time
def walk_dog(first, last):
time.sleep(8)
print(f"你遛完{first} {last}了")
def take_out_trash():
time.sleep(2)
print("你倒完垃圾了")
def get_mail():
time.sleep(4)
print("你取完邮件了")
# 被解释为括号中的字符串
chore1 = threading.Thread(target=walk_dog, args=("Scooby", "Doo"))
chore1.start()
chore2 = threading.Thread(target=take_out_trash)
chore2.start()
chore3 = threading.Thread(target=get_mail)
chore3.start()
print("所有家务都完成了！")
chore1.join()
chore2.join()
chore3.join()
# 你倒完垃圾了
# 你取完邮件了
# 你遛完Scooby Doo了
# 所有家务都完成了！
64. 请求 API 数据 ↩️
PokéAPI
示例：https://pokeapi.co/api/v2/pokemon/pikachu
# 如何使用 Python 连接到 API
import requests # 需要安装 requests：pip install requests
base_url = "https://pokeapi.co/api/v2/"
def get_pokemon_info(name):
pass
pokemon_name = "pikachu"
get_pokemon_info(pokemon_name)
import requests
base_url = "https://pokeapi.co/api/v2/"
def get_pokemon_info(name):
url = f"{base_url}/pokemon/{name}"
response = requests.get(url)
print(response)
pokemon_name = "pikachu"
get_pokemon_info(pokemon_name)
# <Response [200]>
import requests
base_url = "https://pokeapi.co/api/v2/"
def get_pokemon_info(name):
url = f"{base_url}/pokemon/{name}"
response = requests.get(url)
if response.status_code == 200:
print("数据获取成功！")
else:
print(f"数据获取失败，状态码：{response.status_code}")
pokemon_name = "pikachu"
get_pokemon_info(pokemon_name)
# 数据获取成功！
import requests
base_url = "https://pokeapi.co/api/v2/"
def get_pokemon_info(name):
url = f"{base_url}/pokemon/{name}"
response = requests.get(url)
if response.status_code == 200:
pokemon_data = response.json()
print(pokemon_data)
else:
print(f"数据获取失败，状态码：{response.status_code}")
pokemon_name = "pikachu"
get_pokemon_info(pokemon_name)
# {
# "abilities": [
# {
# "ability": {
# "name": "static",
# "url": "https://pokeapi.co/api/v2/ability/9/"
# },
# "is_hidden": false,
# "slot": 1
# },
# {
# "ability": {
# "name": "lightning-rod",
# "url": "https://pokeapi.co/api/v2/ability/31/"
# },
# "is_hidden": true,
# "slot": 3
# }
# ],
# "base_experience": 112,
# "height": 4,
# "id": 25,
# "name": "pikachu",
# "types": [
# {
# "slot": 1,
# "type": {
# "name": "electric",
# "url": "https://pokeapi.co/api/v2/type/13/"
# }
# }
# ],
# "weight": 60
# }
import requests
base_url = "https://pokeapi.co/api/v2/"
def get_pokemon_info(name):
url = f"{base_url}/pokemon/{name}"
response = requests.get(url)
if response.status_code == 200:
pokemon_data = response.json()
return pokemon_data
else:
print(f"数据获取失败，状态码：{response.status_code}")
pokemon_name = "pikachu"
pokemon_info = get_pokemon_info(pokemon_name)
if pokemon_info:
print(f"名称: {pokemon_info['name'].capitalize()}")
print(f"ID: {pokemon_info['id']}")
print(f"身高: {pokemon_info['height']}")
print(f"体重: {pokemon_info['weight']}")
# 名称: Pikachu
# ID: 25
# 身高: 4
# 体重: 60
65. PyQt5 GUI 简介 🖥️
图形用户界面
# PyQt5 简介
import sys
# pip install PyQt5
from PyQt5.QtWidgets import QApplication, QMainWindow
class MainWindow(QMainWindow):
def __init__(self):
super().__init__()
def main():
pass
if __name__ == '__main__':
main()
sys — 系统特定的参数和函数
该模块提供对解释器使用或维护的一些变量的访问，以及与解释器强烈交互的函数。它始终可用。
import sys
from PyQt5.QtWidgets import QApplication, QMainWindow
class MainWindow(QMainWindow):
def __init__(self):
super().__init__()
def main():
app = QApplication(sys.argv)
window = MainWindow()
window.show()
if __name__ == '__main__':
main()
#
# 进程以退出代码 0 结束
sys.argv
传递给 Python 脚本的命令行参数列表。argv[0] 是脚本名称（是否为完整路径名取决于操作系统）。如果使用解释器的 -c 命令行选项执行命令，argv[0] 被设置为字符串 '-c'。如果没有向 Python 解释器传递脚本名称，argv[0] 为空字符串。
import sys
from PyQt5.QtWidgets import QApplication, QMainWindow
from PyQt5.QtGui import QIcon
class MainWindow(QMainWindow):
def __init__(self):
super().__init__()
self.setWindowTitle("我的第一个酷炫 GUI")
self.setGeometry(700, 300, 500, 500)
# self.setGeometry(x, y, 宽度, 高度)
self.setWindowIcon(QIcon("profile_pic.jpg"))
def main():
app = QApplication(sys.argv)
window = MainWindow()
window.show()
sys.exit(app.exec_())
if __name__ == '__main__':
main()
66. PyQt5 标签 🏷️
# PyQt5 QLabel 示例
import sys
from PyQt5.QtWidgets import QApplication, QMainWindow, QLabel
class MainWindow(QMainWindow):
def __init__(self):
super().__init__()
self.setGeometry(700, 300, 500, 500)
label = QLabel("你好", self) # （窗口将作为父控件）
def main():
app = QApplication(sys.argv)
window = MainWindow()
window.show()
sys.exit(app.exec_())
if __name__ == '__main__':
main()
import sys
from PyQt5.QtWidgets import QApplication, QMainWindow, QLabel
from PyQt5.QtGui import QFont
class MainWindow(QMainWindow):
def __init__(self):
super().__init__()
self.setGeometry(700, 300, 500, 500)
label = QLabel("你好", self)
label.setFont(QFont("Arial", 40))
label.setGeometry(0, 0, 500, 100)
label.setStyleSheet("color: #1fff5a;"
"background-color: #6fdcf7;"
"font-weight: bold;"
"font-style: italic;"
"text-decoration: underline;") # 可通过谷歌搜索“颜色选择器”获取颜色代码
def main():
app = QApplication(sys.argv)
window = MainWindow()
window.show()
sys.exit(app.exec_())
if __name__ == '__main__':
main()
import sys
from PyQt5.QtWidgets import QApplication, QMainWindow, QLabel
from PyQt5.QtGui import QFont
from PyQt5.QtCore import Qt
class MainWindow(QMainWindow):
def __init__(self):
super().__init__()
self.setGeometry(700, 300, 500, 500)
label = QLabel("你好", self)
label.setFont(QFont("Arial", 40))
label.setGeometry(0, 0, 500, 100)
label.setStyleSheet("color: #1fff5a;"
"background-color: #6fdcf7;"
"font-weight: bold;"
"font-style: italic;"
"text-decoration: underline;")
# label.setAlignment(Qt.AlignTop) # 垂直顶部对齐
# label.setAlignment(Qt.AlignBottom) # 垂直底部对齐
# label.setAlignment(Qt.AlignVCenter) # 垂直居中对齐
# label.setAlignment(Qt.AlignRight) # 水平右对齐
# label.setAlignment(Qt.AlignHCenter) # 水平居中对齐
# label.setAlignment(Qt.AlignLeft) # 水平左对齐
# label.setAlignment(Qt.AlignHCenter | Qt.AlignTop) # 水平居中 & 垂直顶部
# label.setAlignment(Qt.AlignHCenter | Qt.AlignBottom) # 水平居中 & 垂直底部
# label.setAlignment(Qt.AlignHCenter | Qt.AlignVCenter) # 水平居中 & 垂直居中
label.setAlignment(Qt.AlignCenter) # 水平居中 & 垂直居中
def main():
app = QApplication(sys.argv)
window = MainWindow()
window.show()
sys.exit(app.exec_())
if __name__ == '__main__':
main()
67. PyQt5 图像 📷
import sys
from PyQt5.QtWidgets import QApplication, QMainWindow
class MainWindow(QMainWindow):
def __init__(self):
super().__init__()
self.setGeometry(700, 300, 500, 500)
def main():
app = QApplication(sys.argv)
window = MainWindow()
window.show()
sys.exit(app.exec_())
if __name__ == '__main__':
main()
import sys
from PyQt5.QtWidgets import QApplication, QMainWindow, QLabel
from PyQt5.QtGui import QPixmap
class MainWindow(QMainWindow):
def __init__(self):
super().__init__()
self.setGeometry(700, 300, 500, 500)
label = QLabel(self)
label.setGeometry(0, 0, 250, 250)
# label.setGeometry(x, y, 宽度, 高度)
pixmap = QPixmap("profile_pic.jpg")
label.setPixmap(pixmap)
def main():
app = QApplication(sys.argv)
window = MainWindow()
window.show()
sys.exit(app.exec_())
if __name__ == '__main__':
main()
import sys
from PyQt5.QtWidgets import QApplication, QMainWindow, QLabel
from PyQt5.QtGui import QPixmap
class MainWindow(QMainWindow):
def __init__(self):
super().__init__()
self.setGeometry(700, 300, 500, 500)
label = QLabel(self)
label.setGeometry(0, 0, 250, 250)
# label.setGeometry(x, y, 宽度, 高度)
pixmap = QPixmap("profile_pic.jpg")
label.setPixmap(pixmap)
label.setScaledContents(True)
label.setGeometry((self.width() - label.width()) // 2,
(self.height() - label.height()) // 2,
label.width(),
label.height())
def main():
app = QApplication(sys.argv)
window = MainWindow()
window.show()
sys.exit(app.exec_())
if __name__ == '__main__':
main()
68. PyQt5 布局管理器 🧲
import sys
from PyQt5.QtWidgets import QApplication, QMainWindow
class MainWindow(QMainWindow):
def __init__(self):
super().__init__()
self.setGeometry(700, 300, 500, 500)
def main():
app = QApplication(sys.argv)
window = MainWindow()
window.show()
sys.exit(app.exec_())
if __name__ == '__main__':
main()
import sys
from PyQt5.QtWidgets import (QApplication, QMainWindow, QLabel,
QWidget, QVBoxLayout, QHBoxLayout, QGridLayout)
class MainWindow(QMainWindow):
def __init__(self):
super().__init__()
self.setGeometry(700, 300, 500, 500)
self.initUI()
def initUI(self):
central_widget = QWidget()
self.setCentralWidget(central_widget)
label1 = QLabel("#1", self)
label2 = QLabel("#2", self)
label3 = QLabel("#3", self)
label4 = QLabel("#4", self)
label5 = QLabel("#5", self)
label1.setStyleSheet("background-color: red;")
label2.setStyleSheet("background-color: yellow;")
label3.setStyleSheet("background-color: green;")
label4.setStyleSheet("background-color: blue;")
label5.setStyleSheet("background-color: purple;")
# vbox = QVBoxLayout()
# vbox.addWidget(label1)
# vbox.addWidget(label2)
# vbox.addWidget(label3)
# vbox.addWidget(label4)
# vbox.addWidget(label5)
# central_widget.setLayout(vbox)
# hbox = QHBoxLayout()
# hbox.addWidget(label1)
# hbox.addWidget(label2)
# hbox.addWidget(label3)
# hbox.addWidget(label4)
# hbox.addWidget(label5)
# central_widget.setLayout(hbox)
grid = QGridLayout()
grid.addWidget(label1, 0, 0)
grid.addWidget(label2, 0, 1)
grid.addWidget(label3, 1, 0)
grid.addWidget(label4, 1, 1)
grid.addWidget(label5, 2, 2)
central_widget.setLayout(grid)
def main():
app = QApplication(sys.argv)
window = MainWindow()
window.show()
sys.exit(app.exec_())
if __name__ == '__main__':
main()
69. PyQt5 按钮 🛎️
import sys
from PyQt5.QtWidgets import QMainWindow, QApplication
class MainWindow(QMainWindow):
def __init__(self):
super().__init__()
self.setGeometry(700, 300, 500, 500) # 设置窗口位置和大小
self.initUI()
def initUI(self):
pass
if __name__ == '__main__':
app = QApplication(sys.argv)
window = MainWindow()
window.show()
sys.exit(app.exec_())
import sys
from PyQt5.QtWidgets import QMainWindow, QApplication, QPushButton, QLabel
class MainWindow(QMainWindow):
def __init__(self):
super().__init__()
self.setGeometry(700, 300, 500, 500) # 设置窗口位置和大小
self.button = QPushButton("点击我！", self) # 创建按钮
self.initUI()
def initUI(self):
self.button.setGeometry(150, 200, 200, 100) # 设置按钮位置和大小
self.button.setStyleSheet("font-size: 30px;") # 设置按钮字体大小
self.button.clicked.connect(self.on_click) # 连接按钮点击事件
def on_click(self):
print("按钮被点击！")
self.button.setText("已点击！") # 更改按钮文本
self.button.setDisabled(True) # 禁用按钮
if __name__ == '__main__':
app = QApplication(sys.argv)
window = MainWindow()
window.show()
sys.exit(app.exec_())
import sys
from PyQt5.QtWidgets import QMainWindow, QApplication, QPushButton, QLabel
class MainWindow(QMainWindow):
def __init__(self):
super().__init__()
self.setGeometry(700, 300, 500, 500) # 设置窗口位置和大小
self.button = QPushButton("点击我！", self) # 创建按钮
self.label = QLabel("你好", self) # 创建标签
self.initUI()
def initUI(self):
self.button.setGeometry(150, 200, 200, 100) # 设置按钮位置和大小
self.button.setStyleSheet("font-size: 30px;") # 设置按钮字体大小
self.button.clicked.connect(self.on_click) # 连接按钮点击事件
self.label.setGeometry(150, 300, 200, 100) # 设置标签位置和大小
self.label.setStyleSheet("font-size: 50px;") # 设置标签字体大小
def on_click(self):
self.label.setText("再见") # 点击按钮后更改标签文本
if __name__ == '__main__':
app = QApplication(sys.argv)
window = MainWindow()
window.show()
sys.exit(app.exec_())