装饰器

def outer(func):
    def inner():
        print(‘before‘)
        func()
        print(‘after‘)
    return inner

@outer
def f1():
    print(‘f1‘)

def outer(func):
    def inner():
        print(‘before‘)
        ret = func() # 接收原来f1函数的返回值
        print(‘after‘)
        return ret # 将函数之返回
    return inner

@outer
def f1():
    return ‘f1‘

f1()

def outer(func):
    def inner(a,b): # 加参数
        print(‘before‘)
        ret = func(a,b)  # 加参数
        print(‘after‘)
        return ret  # 将函数之返回

    return inner


@outer
def f1(a, b):
    return a + b

f1(1,2)

def outer(func):
    def inner(*args,**kwargs): # 加参数
        print(‘before‘)
        ret = func(*args,**kwargs)  # 加参数
        print(‘after‘)
        return ret  # 将函数之返回

    return inner


@outer
def f1(a, b):
    return a + b

f1(1,2)

UserInfo = {‘name‘: ‘alex‘, ‘age‘: 18, ‘sex‘: ‘男‘}
Login_flag = False
Login_type = None
# 用户登陆查询用户信息，查看信息之前先登陆,进行后台管理，必须是管理员


def check_login(func):
    def inner(*args,**kwargs):
        if Login_flag is True:
            func()
        else:
            print(‘请先登陆...‘)
    return inner


def check_type(func):
    def inner(*args,**kwargs):
        if Login_type  == 1:
            func()
        else:
            print(‘无权限‘)
    return inner


def login(name, pwd):
    global Login_flag, Login_type
    if name == ‘admin‘:
        Login_flag = True
        Login_type = 1
    elif name == ‘alex‘ and pwd == ‘123‘:
        Login_flag = True
    else:
        pass


@check_login
def select():
    for li in UserInfo.keys():
        print(UserInfo[li])


@check_login
@check_type
def admin():
    print(‘后台管理‘)

inp = input(‘1:登陆 2:查看用户，3:后台管理\n>>>‘)
name = input(‘UserName:>>>‘)
pwd = input(‘PassWord:>>>‘)
if inp == ‘1‘:
    login(name, pwd)
elif inp == ‘2‘:
    select()
elif inp == ‘3‘:
    # login(name, pwd)
    login(name, pwd)
    admin()