Python装饰器详细介绍

from functools import wraps
def test_wrapper(func):
    @wraps(func)
    def inner_wrapper():
        print("Use inner_wrapper")
        func()
    return inner_wrapper
@test_wrapper
def func2():
    print("Use func2") 

def test_wrapper2(func):
    def inner_wrapper():
        pass
    return inner_wrapper
@test_wrapper2
def func3():
    pass

def A(func):
	pass
@A
def func():
	pass
func()
"""
就相当于是
把func()的调用
换成了A(func)(),故这里A函数返回的一定是一个可以被调用(call)的函数,否则会报错
"""

from functools import wraps
# 在装饰器中使用额外参数
def another_keyword(another_keyword=None):
    def test_func(func):
        @wraps(func)
        def func_wrapper():
            if another_keyword == 1:
                print("Use another_keyword")
            else:
                print("Not use another_keyword")
            print("Using func_wrapper")
            func()
        return func_wrapper
    return test_func
@another_keyword(another_keyword=1)
def func():
    print("Use func")

another_keyword(another_keyword=1)(func)()

from functools import wraps
class cls_wrapper(object):
    def __init__(self):
        pass
    def __call__(self, func):
        @wraps(func)
        def inner_wrapper():
            func()
        return inner_wrapper
@cls_wrapper()
def func4():
    print("Use func4")