一、装饰器无参数

1.原函数无参数

def wrap_in_tag_b(fn): # wrap_in_tag_b 是真正的装饰器    def wrapped():        return "" + fn() + ""    return wrappeddef wrap_in_tag_i(fn):    def wrapped():        return "" + fn() + ""    return wrapped@wrap_in_tag_b@wrap_in_tag_idef hello():    return "hello"print(hello()) # returns "hello world"

2.原函数带参数

def wrap_in_tag_b(fn):    def wrapped(arg): # arg 是原函数参数        return "" + fn(arg) + ""    return wrappeddef wrap_in_tag_i(fn):    def wrapped(arg): # arg 是原函数参数        return "" + fn(arg) + ""    return wrapped@wrap_in_tag_b@wrap_in_tag_idef hello(name):    return "hello {}".formar(name)print(hello('Jack'))

二、装饰器带参数

1.原函数无参数

def wrap_in_tag(deco_arg):    # 装饰器参数：deco_arg    # 可以在任意位置使用    def real_decorator(func):  # real_decorator才是即将返回的真正的装饰器　　　　# 原函数参数：func_arg 　　　　# 只可以在此位置使用 　　　　def wrapped() :            return "<{0}>{1}
     ".format(deco_arg, func())        return wrapped    return real_decorator@wrap_in_tag('b')@wrap_in_tag('i')def hello():    return "hello"    print(hello())

2.原函数带参数

def wrap_in_tag(deco_arg):    # 装饰器参数：deco_arg    # 可以在任意位置使用    def real_decorator(func):  # real_decorator才是即将返回的真正的装饰器        def wrapped(func_arg):            # 原函数参数：func_arg            # 只可以在此位置使用            return "<{0}>{1}
     ".format(deco_arg, func(func_arg))        return wrapped    return real_decorator    @wrap_in_tag('b')@wrap_in_tag('i')def hello(name):    return "hello {}".format(name)    print(hello('Jack'))

三、装饰器类

1.原函数无参数

class wrap_in_tag(object):    def __init__(self, deco_arg):        self.tag = deco_arg  # 装饰器参数：deco_arg    def __call__(self, func):        def newf(): # 原函数无参数            return "<{0}>{1}
     ".format(self.tag, func())        return newf@wrap_in_tag('b')@wrap_in_tag('i')def hello():    return 'hello' print(hello())

2.原函数带参数

class wrap_in_tag(object):    def __init__(self, deco_arg):        self.tag = deco_arg # 装饰器参数：deco_arg            def __call__(self, func):        def newf(func_arg): # 原函数参数: func_arg            return "<{0}>{1}
     ".format(self.tag, func(func_arg))        return newf@wrap_in_tag('b')@wrap_in_tag('i')def hello(name):    return "hello {}".format(name) print(hello('Jack'))

四、用装饰器装饰类

1.用函数作为装饰器

def wrap_in_tag(deco_arg):    def real_decorator(func):        def wrapped(self, func_arg): # 类方法接收第一个参数都是self，这个必须有，而无论func_arg是否有!!!            return "<{0}>{1}
     ".format(deco_arg, func(func_arg))        return wrapped    return real_decoratorclass foo(object):        @wrap_in_tag('b')    @wrap_in_tag('i')    def hello(self, name):        return 'hello {}".format(name)        @wrap_in_tag('b')    @wrap_in_tag('i')    def byebye(self, name):        return 'byebye {}".format(name)    f = foo()print(f.hello('Jack')

2.用类作为装饰器

class wrap_in_tag(object):    def __init__(self, deco_arg):        self.tag = deco_arg            def __call__(self, func):        def newf(slf, func_arg): # slf必须！self被占用了，那就给第一个参数另一个名字slf（随便）            return "<{0}>{1}
     ".format(self.tag, func(func_arg))        return newf                        class foo(object):        @wrap_in_tag('b')    @wrap_in_tag('i')    def hello(self, name):        return 'hello {}".format(name)        @wrap_in_tag('b')    @wrap_in_tag('i')    def byebye(self, name):        return 'byebye {}".format(name)

f = foo()print(f.hello('Jack'))