装饰器-示例

!/usr/bin/env python

-- coding: utf-8 --

@Time : 2018/6/3 0003 11:47

@Author : Anthony.Waa

@Site :

@File : test.py

@Software: PyCharm

示例1：

带状态的装饰器

from functools import wraps
import time
def timeout(flag1):
    def timmer(f):
        '''
        此函数用于显示被装饰函数的运行效率，打印运行市场即为正确
        :param f: f = JD()
        :return:
        '''
        @wraps(f)
        def inner(*args,**kwargs):
            if flag1:
                start_time = time.time()
                ret = f(*args,**kwargs)
                end_time = time.time()
                print('此函数的执行效率%s' % (end_time - start_time))
                return ret
            else:
                ret = f(*args, **kwargs)
                return ret
        return inner
    return timmer


flag = False
@timeout(flag)
def JD():
    '''
    此处为被装饰函数
    :return:
    '''
    time.sleep(0.3)
    print('非常复杂......')
    return 666

JD()

示例2

带参数的装饰器

from functools import wraps
import time
def timeout(flag1):
    def timmer(f):
        '''
        此函数用于显示被装饰函数的运行效率，打印运行市场即为正确
        :param f: f = JD()
        :return:
        '''
        @wraps(f)
        def inner(*args,**kwargs):
            if flag1:
                start_time = time.time()
                ret = f(*args,**kwargs)
                end_time = time.time()
                print('此函数的执行效率%s' % (end_time - start_time))
                return ret
            else:
                ret = f(*args, **kwargs)
                return ret
        return inner
    return timmer



@timeout('京东')
def JD():
    '''
    此处为被装饰函数
    :return:
    '''
    time.sleep(0.3)
    print('我是京东......')
    return 666

@timeout('淘宝')
def taobao():
    '''
    此处为被装饰函数
    :return:
    '''
    time.sleep(0.3)
    print('我是淘宝......')
    return 666
JD()
taobao()

示例3：

多个装饰器装饰一个函数

import time
def wrapper1(func1):  # func = inner2
    def inner1():
        print('wrapper1 ,before func') # 1
        func1()  # inner2
        print('wrapper1 ,after func')   # 7
    return inner1


def wrapper2(func2):  # func2 = inner3
    def inner2():
        print('wrapper2 ,before func')  # 2
        func2()  # inner3
        print('wrapper2 ,after func')  # 6
    return inner2

def wrapper3(func3):  # func3 = index()
    def inner3():
        print('wrapper3 ,before func')  # 3
        func3()  # index()
        print('wrapper3 ,after func')  # 5
    return inner3



@wrapper1 # index = wrapper1(inner2)
@wrapper2 # index = wrapper2(inner3)
@wrapper3 # index = wrapper3(index)
def index():
    print('in my heart') # 4
    time.sleep(0.3)



index()