python学习日记：day11----装饰器进阶

1、wraps

from functools import wraps
def wrapper(func):  #func = holiday
    @wraps(func)#输出holiday的函数名
    def inner(*args,**kwargs):
        print('在被装饰的函数执行之前做的事')
        ret = func(*args,**kwargs)
        print('在被装饰的函数执行之后做的事')
        return ret
    return inner

@wrapper   #holiday = wrapper(holiday)
def holiday(day):
    '''这是一个放假通知'''
    print('全体放假%s天'%day)
    return '好开心'

print(holiday.__name__)
print(holiday.__doc__)
ret = holiday(3)   #inner
print(ret)


# def wahaha():
#     '''
#     一个打印娃哈哈的函数
#     :return:
#     '''
#     print('娃哈哈')

# print(wahaha.__name__) #查看字符串格式的函数名
# print(wahaha.__doc__)  #document。查看函数的注释内容

2、带参数的装饰器

import time
flag = True
def timmer_out(flag):
    def timmer(func):
        def inner(*args,**kwargs ):
            if flag
                start == time.time()
                ret =func(*args,**kwargs)
                end =time.time()
                print(end-start)
                return ret
            else:
                ret=func(*args,**kwargs )
                return ret
        return inner
    return timmer
@timmer_out(flag)#----》# timmer = timmer_out(FLAGE)----> #func1 = timmer(func1)
def func1():
        time.time(0.1)
        print('哇哈哈哈')

3,多个装饰器装饰一个函数

def wrapper1(func):
    def inner1():
        print('wrapper1 ,before func')
        ret = func()
        print('wrapper1 ,after func')
        return ret
    return inner1

def wrapper2(func):
    def inner2():
        print('wrapper2 ,before func')
        ret = func()
        print('wrapper2 ,after func')
        return ret
    return inner2

def wrapper3(func):
    def inner3():
        print('wrapper3 ,before func')
        ret = func()
        print('wrapper3 ,after func')
        return ret
    return inner3

@wrapper3
@wrapper2
@wrapper1
def f():
    print('in f')
    return '哈哈哈'

print(f())