Python | 属性包装器

1. 普通方法

1.1. 装饰器无参数

def warp(callback):
    def f(*args, **kwargs):
        print('调用之前')
        callback(*args, **kwargs)
        print('调用之后')

    return f


@warp
def hello(name: str = '未设置'):
    print(f'hello {name}')


if __name__ == '__main__':
    hello('yimt')

Output

调用之前
hello yimt
调用之后

1.2. 装饰器有参数

def warp(name: str):
    def f1(callback):
        def f2(*args, **kwargs):
            kwargs['name'] = name
            print('调用之前')
            callback(*args, **kwargs)
            print('调用之后')

        return f2

    return f1


@warp('yimt')
def hello(name: str = '未设置'):
    print(f'hello {name}')


if __name__ == '__main__':
    hello()

Output

调用之前
hello yimt
调用之后

2. 类方法

2.1. 装饰器不带参数

def wrap(callback):
    def f(*args, **kwargs):
        print('调用之前')
        r = callback(*args, **kwargs)
        print('调用之后')
        return r

    return f


class A:
    @wrap
    def hello(self, name: str = '未设置'):
        print(f'hello {name}')


a = A()
a.hello('yimt')

Output

调用之前
hello yimt
调用之后

2.2. 装饰器带参数

def wrap(name: str):
    def f1(callback):
        def f2(*args, **kwargs):
            kwargs['name'] = name
            print('调用之前')
            r = callback(*args, **kwargs)
            print('调用之后')
            return r

        return f2

    return f1


class A:
    @wrap('yimt')
    def hello(self, name: str = '未设置'):
        print(f'hello {name}')


a = A()
a.hello()

Output

调用之前
hello yimt
调用之后

3. 多装饰器

def warp_a(callback):
    def f(*args, **kwargs):
        print('a调用之前')
        callback(*args, **kwargs)
        print('a调用之后')

    return f


def warp_b(callback):
    def f(*args, **kwargs):
        print('b调用之前')
        callback(*args, **kwargs)
        print('b调用之后')

    return f


@warp_a
@warp_b
def hello(name: str = '未设置'):
    print(f'hello {name}')


if __name__ == '__main__':
    hello('yimt')

Output

a调用之前
b调用之前
hello yimt
b调用之后
a调用之后