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 "<b>" + fn() + "</b>" return wrapped def wrap_in_tag_i(fn): def wrapped(): return "<i>" + fn() + "</i>" return wrapped @wrap_in_tag_b @wrap_in_tag_i def hello(): return "hello" print(hello()) # returns "<b><i>hello world</i></b>"
2.原函数带参数
def wrap_in_tag_b(fn): def wrapped(arg): # arg 是原函数参数 return "<b>" + fn(arg) + "</b>" return wrapped def wrap_in_tag_i(fn): def wrapped(arg): # arg 是原函数参数 return "<i>" + fn(arg) + "</i>" return wrapped @wrap_in_tag_b @wrap_in_tag_i def 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}</{0}>".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}</{0}>".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}</{0}>".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}</{0}>".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}</{0}>".format(deco_arg, func(func_arg)) return wrapped return real_decorator 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')
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}</{0}>".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'))
本文转自罗兵博客园博客,原文链接:http://www.cnblogs.com/hhh5460/p/5147103.html,如需转载请自行联系原作者