一、函數裝飾器

1）帶參數的裝飾器：

import time
FLAGE = False
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 = timmer_out(FLAGE)
@timmer_out(FLAGE)    #wahaha = timmer(wahaha)
def wahaha():
    time.sleep(0.1)
    print(‘wahahahahahaha‘)

@timmer_out(FLAGE)
def erguotou():
    time.sleep(
 
0.1)
    print(‘erguotoutoutou‘)

wahaha()
erguotou()

2）多個裝飾器裝飾同一個函數：

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())

#記錄用戶的登錄情況
#計算這個函數的執行時間

3）裝飾器的固定格式——wraps版：

from functools import wraps
def wrapper(func):  #func = holiday
    @wraps(func)
    def inner(*args,**kwargs):
        print(‘在被裝飾的函數執行之前做的事‘)
        ret = func(*args,**kwargs)
        print(‘在被裝飾的函數執行之後做的事‘)
        return ret
    return inner

@wrapper   #holiday = wrapper(holiday)
def holiday(day):
    ‘‘‘這是一個放假通知‘‘‘
    print(‘全體放假%s天‘%day)
    return ‘好開心‘

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


# def wahaha():
#     ‘‘‘
#     一個打印娃哈哈的函數
#     :return:
#     ‘‘‘
#     print(‘娃哈哈‘)

# print(wahaha.__name__) #查看字符串格式的函數名
# print(wahaha.__doc__)  #document

函數裝飾器的擴展