原来Python类还有这么多花样

"""metaclass的作用是指定当前类由谁来创建"""

# 第一种创建类的方式class Foo(object):    name = "小强"     # 类的静态字段

def func(self):        return 666

val = Foo()print(val.name)

# 第二种创建类的方式Foo1 = type("Foo", (object,), {"name": "小强", "func": lambda self: 666})

val1 = Foo1()print(val1.name)

# 2.自定义typeclass YouType(type):    pass

class Foo2(object, metaclass=YouType):    # metaclass指定当前继承类    name = "小老鼠"

def func(self):        return "猫不抓"

val2 = Foo2()print(val2.name)

Foo3 = YouType("Foo", (object,), {"name": "小老鼠", "func": lambda self: "猫不抓"})

val3 = Foo3()print(val3.name)

# 3.metaclassclass MyType(type):

def __init__(self, *args, **kwargs):        super(MyType, self).__init__(*args, **kwargs)

def __call__(cls, *args, **kwargs):        obj = cls.__new__(cls)        cls.__init__(obj, *args, **kwargs)        return obj

class Foo4(object, metaclass=MyType):    name = "旺财"

def __init__(self):        pass

def __new__(cls, *args, **kwargs):        return object.__new__(cls)

def func(self):        return 666

# Foo4是MyType的一个对象obj = Foo4()print(obj.name)

原文地址：https://www.cnblogs.com/Guishuzhe/p/9783188.html