Python学习笔记（12）装饰器

标签：wrap   port   decorator   alt   func   装饰器   传递   参数   div   

import time

def show_time(f):

    def inner(a, b):
        start = time.time()
        f(a, b)
        end = time.time()
        print(‘spend %s‘ % (end - start))

    return inner


@show_time           # add = show_time(add)
def add(a, b):
    print(a + b)
    time.sleep(1)


add(3, 4)

import time
import functools


def log(func):
    @functools.wraps(func)
    def wapper():
        print(‘%s‘ % func.__name__)
        func()
    return wapper


@log
def now():
    print(time.strftime(‘%Y-%m-%d %H:%M:%S‘, time.localtime()))

2018-04-27 21:56:56
now

functools.wraps 相当于写 wapper.__name__ = now.__name__

不然结果会成为

import time
import functools


def log(func):
    # @functools.wraps(func)
    def wapper():
        print(‘%s‘ % func.__name__)
        func()
    return wapper


@log
def now():
    print(time.strftime(‘%Y-%m-%d %H:%M:%S‘, time.localtime()))


now()
print(now.__name__)

2018-04-27 21:58:32
wapper

装饰器传递参数 如下例

Python学习笔记（12）装饰器

标签：wrap   port   decorator   alt   func   装饰器   传递   参数   div   

原文地址：https://www.cnblogs.com/thyh/p/8964837.html