2021-06-01 通过类去实现装饰器__call__.

1. 含有__init__的类

class MyClass:
    a = "cherry"

    def __init__(self,age,sex):
        self.age = age
        self.sex = sex

    def say(self):
        print("hello")

obj = MyClass(age=10,sex="male") 
# 给类对象初始化赋值

2. 不添加call方法

class MyDecorator:
    def __init__(self, func):
        self.func = func
@MyDecorator  # work1 =MyDecorator(work1) # 相当于给类对象初始化赋值，参考1中的解释
def work1(a, b):
    print("--这是原功能函数")
    return a + b
work1 = MyDecorator(work1)
print(work1)  # <__main__.MyDecorator object at 0x032F2448> 返回的是MyDecorator多的对象

print(work1())  

TypeError: ‘MyDecorator’ object is not callable

3.如果想要被调用，需要加入__call__方法

class MyDecorator:
    def __init__(self, func):
        self.func = func

    **def __call__(self, *args, **kwargs):
        print("装饰器扩展的功能1")
        res = self.func(*args, **kwargs)
        print("装饰器扩展的功能2")
        return res**


@MyDecorator  # work1 =MyDecorator(work1) # 相当于给类对象初始化赋值
def work1(a, b):
    print("--这是原功能函数")
    return a + b
work1 = MyDecorator(work1)
print(work1)  # <__main__.MyDecorator object at 0x032F2448> 返回的是MyDecorator多的对象

print(work1())  # 此时就不会报错了