Python之路-函数基础01

一： 装饰器

1：装饰器模板

def wrapper(func):
    def inner(*args,**kwargs):
        ret =func(*args,**kwargs)
        return ret
    return inner

开放封闭原则

对扩展是开放的

对修改时封闭的

import  time

def wrapper(func):
    def innner(*args,**kwargs):
        start = time.time()
        time.sleep(1)
        func(*args,**kwargs)
        end = time.time()
        print(end-start)
    return innner

@wrapper # func = wrapper(func)
def func():
    print('hello world')
func()

# 给函数加上认证功能，登录一次就可以多次调用函数

FLAG = False
def login(func):
    def innner(*args,**kwargs):
        global FLAG
        if FLAG:
            ret =func(*args,**kwargs)
            return func
        else:
            username = input('username: ')
            password = input('password: ')
            if username == 'wangys' and password == 'wangys':
                FLAG = True
                ret =func(*args,**kwargs)
                return func
            else:print("用户名密码错误")
    return innner


@login
def shoplist_add():
    print('增加一个商品')
@login
def shoplist_delete():
    print('删除一个商品')



shoplist_add()
shoplist_delete()