Python中很常用的100个函数整理

Python 内置函数提供了强大的工具，涵盖数据处理、数学运算、迭代控制、类型转换等。本文总结了 100 个常用内置函数，并配备示例代码，提高编程效率。

1. abs() 取绝对值

print(abs(-10))  # 10

2. all() 判断所有元素是否为真

print(all([True, 1, "hello"]))  # True
print(all([True, 0, "hello"]))  # False

3. any() 判断任意元素是否为真

print(any([False, 0, "", None]))  # False
print(any([False, 1, ""]))  # True

4. ascii() 返回对象的 ASCII 表示

print(ascii("你好"))  # '\u4f60\u597d'

5. bin() 十进制转二进制

print(bin(10))  # '0b1010'

6. bool() 转换为布尔值

print(bool([]))  # False
print(bool(1))  # True

7. bytearray() 创建字节数组

ba = bytearray([65, 66, 67])
print(ba)  # bytearray(b'ABC')

8. bytes() 创建不可变字节序列

b = bytes("hello", encoding="utf-8")
print(b)  # b'hello'

9. callable() 判断对象是否可调用

def func(): pass
print(callable(func))  # True
print(callable(10))  # False

10. chr() 获取 Unicode 码对应的字符

print(chr(97))  # 'a'

11. ord() 获取字符的 Unicode 编码

print(ord('a'))  # 97

12. complex() 创建复数

print(complex(1, 2))  # (1+2j)

13. dict() 创建字典

d = dict(name="Alice", age=25)
print(d)  # {'name': 'Alice', 'age': 25}

14. dir() 获取对象所有属性和方法

print(dir([]))  # ['append', 'clear', 'copy', ...]

15. divmod() 取商和余数

print(divmod(10, 3))  # (3, 1)

16. enumerate() 生成索引和值

lst = ["a", "b", "c"]
for i, v in enumerate(lst):
    print(i, v)

17. eval() 计算字符串表达式

expr = "3 + 4"
print(eval(expr))  # 7

18. filter() 过滤序列

nums = [1, 2, 3, 4, 5]
even_nums = list(filter(lambda x: x % 2 == 0, nums))
print(even_nums)  # [2, 4]

19. float() 转换为浮点数

print(float("3.14"))  # 3.14

20. format() 格式化字符串

print(format(10000, ","))  # '10,000'
21. frozenset() 创建不可变集合
fs = frozenset([1, 2, 3])
print(fs)

22. globals() 获取全局变量

print(globals())

23. hasattr() 检查对象是否有属性

class Person:
    name = "Alice"print(hasattr(Person, "name"))  # True

24. hash() 获取哈希值

print(hash("hello"))  

25. help() 查看帮助

help(print)

26. hex() 十进制转十六进制

print(hex(255))  # '0xff'

27. id() 获取对象的唯一标识符

a = 10
print(id(a))

28. input() 获取用户输入

name = input("请输入你的名字: ")
print("你好, " + name)

29. int() 转换为整数

print(int("123"))  # 123

30. isinstance() 检查对象类型

print(isinstance(123, int))  # True

31. issubclass() 检查是否是子类

class A: pass
class B(A): pass
print(issubclass(B, A))  # True

32. iter() 获取迭代器

lst = [1, 2, 3]
it = iter(lst)
print(next(it))  # 1

33. len() 获取长度

print(len([1, 2, 3]))  # 3

34. list() 创建列表

print(list("hello"))  # ['h', 'e', 'l', 'l', 'o']

35. locals() 获取局部变量

def func():
    a = 10
    print(locals())

func()

36. map() 对序列中的每个元素进行操作

nums = [1, 2, 3, 4]
squared = list(map(lambda x: x ** 2, nums))
print(squared)  # [1, 4, 9, 16]

37. max() 返回最大值

print(max([10, 20, 5]))  # 20
print(max("python"))  # 'y'

38. min() 返回最小值

print(min([10, 20, 5]))  # 5
print(min("python"))  # 'h'

39. next() 获取迭代器的下一个元素

it = iter([10, 20, 30])
print(next(it))  # 10
print(next(it))  # 20

40. object() 创建一个新对象

obj = object()
print(obj)  # <object object at 0x...>

41. oct() 十进制转八进制

print(oct(10))  # '0o12'

42. open() 打开文件

with open("test.txt", "w") as f:
    f.write("Hello, Python!")

43. pow() 计算指数幂

print(pow(2, 3))  # 8
print(pow(2, 3, 5))  # (2^3) % 5 = 3

44. print() 打印输出

print("Hello", "Python", sep="-")  # Hello-Python

45. range() 生成范围序列

print(list(range(1, 10, 2)))  # [1, 3, 5, 7, 9]

46. repr() 返回对象的字符串表示

print(repr("Hello\nWorld"))  # "'Hello\\nWorld'"

47. reversed() 反转序列

print(list(reversed([1, 2, 3, 4])))  # [4, 3, 2, 1]

48. round() 四舍五入

print(round(3.14159, 2))  # 3.14

49. set() 创建集合

print(set([1, 2, 2, 3]))  # {1, 2, 3}

50. setattr() 设置对象属性

class Person:
    pass
p = Person()
setattr(p, "age", 25)
print(p.age)  # 25

51. slice() 创建切片对象

lst = [10, 20, 30, 40]
s = slice(1, 3)
print(lst[s])  # [20, 30]

52. sorted() 排序

print(sorted([3, 1, 4, 2]))  # [1, 2, 3, 4]
print(sorted("python"))  # ['h', 'n', 'o', 'p', 't', 'y']

53. staticmethod() 定义静态方法

class Math:
    @staticmethod
    def add(x, y):
        return x + yprint(Math.add(3, 4))  # 7

54. str() 转换为字符串

print(str(123))  # '123'
print(str([1, 2, 3]))  # '[1, 2, 3]'

55. sum() 计算总和

print(sum([1, 2, 3, 4]))  # 10

56. super() 调用父类方法

class Parent:
    def greet(self):
        print("Hello from Parent")

class Child(Parent):
    def greet(self):
        super().greet()
        print("Hello from Child")

c = Child()
c.greet()

57. tuple() 创建元组

print(tuple([1, 2, 3]))  # (1, 2, 3)

58. type() 获取对象类型

print(type(123))  # <class 'int'>

59. vars() 获取对象的 dict 属性

class Person:
    def __init__(self, name, age):
        self.name = name
        self.age = agep = Person("Alice", 25)
print(vars(p))  # {'name': 'Alice', 'age': 25}

60. zip() 合并多个可迭代对象

names = ["Alice", "Bob"]
ages = [25, 30]
print(list(zip(names, ages)))  # [('Alice', 25), ('Bob', 30)]

61. import() 动态导入模块

math_module = __import__("math")
print(math_module.sqrt(16))  # 4.0

62. delattr() 删除对象的属性

class Person:
    age = 25
delattr(Person, "age")
print(hasattr(Person, "age"))  # False

63. exec() 执行字符串代码

code = "x = 10\ny = 20\nprint(x + y)"
exec(code)  # 30

64. memoryview() 创建内存视图对象

b = bytearray("hello", "utf-8")
mv = memoryview(b)
print(mv[0])  # 104

65. round() 取整

print(round(4.567, 2))  # 4.57

66. breakpoint() 设置调试断点

x = 10
breakpoint()  # 进入调试模式
print(x)

67. classmethod() 定义类方法

class Person:
    name = "Unknown"
    @classmethod
    def set_name(cls, name):
        cls.name = namePerson.set_name("Alice")
print(Person.name)  # Alice

68. compile() 编译字符串为代码对象

code = "print('Hello, World!')"
compiled_code = compile(code, '<string>', 'exec')
exec(compiled_code)  # Hello, World!

69. complex() 创建复数

c = complex(3, 4)
print(c)  # (3+4j)

70. del 删除对象

x = 10
del x
# print(x)  # NameError: name 'x' is not defined

71. ellipsis 省略号对象

def func():
    ...
print(func())  # None

72. float.fromhex() 将十六进制转换为浮点数

print(float.fromhex('0x1.8p3'))  # 12.0

73. format_map() 使用映射对象格式化字符串

class Person:
    age = 25
print(getattr(Person, "age"))  # 25

74. getattr() 获取对象属性

class Person:
    age = 25
print(getattr(Person, "age"))  # 25

75. is 判断是否是同一个对象

a = [1, 2, 3]
b = a
print(a is b)  # True

76. issubclass() 判断是否是子类

class A: pass
class B(A): passprint(issubclass(B, A))  # True

77. iter() 创建迭代器

lst = [1, 2, 3]
it = iter(lst)
print(next(it))  # 1

78. len() 获取长度

print(len([1, 2, 3]))  # 3

79. memoryview() 创建内存视图

b = bytearray("hello", "utf-8")
mv = memoryview(b)
print(mv[0])  # 104

80. object() 创建基础对象

obj = object()
print(obj)

81. print(*objects, sep, end, file, flush) 高级用法

print("Hello", "World", sep="-", end="!")  # Hello-World!

82. property() 创建只读属性

class Person:
    def __init__(self, name):
        self._name = name
    @property
    def name(self):
        return self._namep = Person("Alice")
print(p.name)  # Alice

83. repr() 返回字符串表示

print(repr("Hello\nWorld"))  # 'Hello\nWorld'

84. round() 四舍五入

print(round(4.567, 2))  # 4.57

85. set() 创建集合

s = set([1, 2, 3, 3])
print(s)  # {1, 2, 3}

86. setattr() 设置对象属性

class Person:
    pass
p = Person()
setattr(p, "age", 30)
print(p.age)  # 30

87. slice() 创建切片对象

lst = [10, 20, 30, 40]
s = slice(1, 3)
print(lst[s])  # [20, 30]

88. sorted() 排序

print(sorted([3, 1, 4, 2]))  # [1, 2, 3, 4]

89. staticmethod() 定义静态方法

class Math:
    @staticmethod
    def add(x, y):
        return x + yprint(Math.add(3, 4))  # 7

90. sum() 计算总和

print(sum([1, 2, 3, 4]))  # 10

91. super() 调用父类方法

class Parent:
    def greet(self):
        print("Hello from Parent")
class Child(Parent):
    def greet(self):
        super().greet()
        print("Hello from Child")
c = Child()
c.greet()

92. tuple() 创建元组

print(tuple([1, 2, 3]))  # (1, 2, 3)

93. type() 获取对象类型

print(type(123))  # <class 'int'>

94. vars() 获取对象属性字典

class Person:
    def __init__(self, name, age):
        self.name = name
        self.age = agep = Person("Alice", 25)
print(vars(p))  # {'name': 'Alice', 'age': 25}

95. zip() 压缩多个可迭代对象

names = ["Alice", "Bob"]
ages = [25, 30]
print(list(zip(names, ages)))  # [('Alice', 25), ('Bob', 30)]

96. callable() 检测对象是否可调用

def foo():
    pass
print(callable(foo))  # True

97. bin() 转换为二进制

print(bin(10))  # '0b1010'

98. hex() 转换为十六进制

print(hex(255))  # '0xff'

99. oct() 转换为八进制

print(oct(8))  # '0o10'