参考网址
> http://www.cnblogs.com/rhcad/archive/2011/12/21/2295507.html
> http://www.cnblogs.com/huxi/archive/2011/03/01/1967600.html
简述
- 装饰器的特点就是对已有的对象添加额外功能，且不修改对象内部代码
- 使用装饰器语法糖(＠XXXXX)装饰后，相当于嵌套闭合函数语法糖指向的函数也就是一个高阶函数，
被装饰函数就是传入的函数实参
一：不带参数
#!/usr/bin/python
# -*- coding:utf-8 -*-
# 16 Oct. 2015
# Author: Huang Junkai
import time
def time_calu1(func):
def _extra():
start = time.clock()
func()
end = time.clock()
print 'total time:', end - start
return _extra
def time_calu2(func):
start = time.clock()
func()
end = time.clock()
print 'total time:', end - start
return func
@time_calu2
def func():
print 'Wow! Success'
func()
func()
看看两个装饰器time_calu1与time_calu2的区别：
前者是一次性的，只对第一个func()有效，即28~19行代码等效于func = time_calu1(func); func()
而后者可保证对每次调用的func()，都有效
二：带参数
代码：
#!/usr/bin/python
-- coding:utf-8 --
# 16 Oct. 2015
# Author: Huang Junkai
import time
def time_calu1(func):
def _extra(a, b):
start = time.clock()
result = func(a, b)
end = time.clock()
print 'used:', end - start
return result
return _extra
def time_calu2(func):
start = time.clock()
func()
end = time.clock()
print 'used:', end - start
return func
@time_calu1
def foo(a, b):
# print 'Wow! Success: the result is %s' % (a + b)
return a + b
result = foo(1, 2)
print result
