Python函数07/有参装饰器/多个装饰器装饰一个函数

Python函数07/有参装饰器/多个装饰器装饰一个函数

目录

• Python函数07/有参装饰器/多个装饰器装饰一个函数
  • 内容大纲
  • 1.有参装饰器
  • 2.多个装饰器装饰一个函数
  • 3.今日总结
  • 3.今日练习

内容大纲

1.有参装饰器

2.多个装饰器装饰一个函数

1.有参装饰器

# def auth(argv):
#     def wrapper(func):
#         def inner(*args,**kwargs):
#             func(*args,**kwargs)
#         return inner
#     return wrapper


# login_dic = {
#     "username": None,
#     "flag": False
# }
# def auth(argv): # argv == foo
#     def wrapper(func):
#         def inner(*args,**kwargs):
#             if login_dic["flag"]:
#                 func(*args,**kwargs)
#             else:
#                 if argv == "QQ":
#                     user = input("username:")
#                     pwd = input("password:")
#                     if user == "alex" and pwd == "alex123":  # qq
#                         login_dic["flag"] = True
#                         login_dic["username"] = user
#                         func(*args,**kwargs)
#                     else:
#                         print("用户名或密码错误!")
#                 elif argv == "微信":
#                     user = input("username:")
#                     pwd = input("password:")
#                     if user == "1351101501" and pwd == "alex":  # 微信
#                         login_dic["flag"] = True
#                         login_dic["username"] = user
#                         func(*args, **kwargs)
#                     else:
#                         print("用户名或密码错误!")
#                 elif argv == "抖音":
#                     user = input("username:")
#                     pwd = input("password:")
#                     if user == "alexdsb" and pwd == "alex":  # 抖音
#                         login_dic["flag"] = True
#                         login_dic["username"] = user
#                         func(*args, **kwargs)
#                     else:
#                         print("用户名或密码错误!")
#                 else:
#                     user = input("username:")
#                     pwd = input("password:")
#                     if user == "alexdsb@dsb.com" and pwd == "alex":  # 邮箱
#                         login_dic["flag"] = True
#                         login_dic["username"] = user
#                         func(*args, **kwargs)
#                     else:
#                         print("用户名或密码错误!")
#
#         return inner
#     return wrapper
#
# # 错误的案例
# @auth # foo = auth(foo)
# def foo():
#     print("这是一个被装饰的函数")
#
# foo()


login_dic = {
    "username": None,
    "flag": False
}
# 正确的案例
msg = """
QQ
微信
抖音
邮箱
请输入您要选择登陆的app:
"""
chose = input(msg).upper()

def auth(argv):
    def wrapper(func):
        def inner(*args,**kwargs):
            if login_dic["flag"]:
                func(*args,**kwargs)
            else:
                if argv == "QQ":
                    print("欢迎登陆QQ")
                    user = input("username:")
                    pwd = input("password:")
                    if user == "alex" and pwd == "alex123":  # qq
                        login_dic["flag"] = True
                        login_dic["username"] = user
                        func(*args,**kwargs)
                    else:
                        print("用户名或密码错误!")
                elif argv == "微信":
                    print("欢迎登陆微信")
                    user = input("username:")
                    pwd = input("password:")
                    if user == "1351101501" and pwd == "alex":  # 微信
                        login_dic["flag"] = True
                        login_dic["username"] = user
                        func(*args, **kwargs)
                    else:
                        print("用户名或密码错误!")
                elif argv == "抖音":
                    print("来了,老弟!")
                    user = input("username:")
                    pwd = input("password:")
                    if user == "alexdsb" and pwd == "alex":  # 抖音
                        login_dic["flag"] = True
                        login_dic["username"] = user
                        func(*args, **kwargs)
                    else:
                        print("用户名或密码错误!")
                else:
                    print("欢迎登陆dab邮箱")
                    user = input("username:")
                    pwd = input("password:")
                    if user == "alexdsb@dsb.com" and pwd == "alex":  # 邮箱
                        login_dic["flag"] = True
                        login_dic["username"] = user
                        func(*args, **kwargs)
                    else:
                        print("用户名或密码错误!")
        return inner
    return wrapper
@auth("QQ")
def foo():
    print("这是一个被装饰的函数")

# wrapper = auth(chose)
# foo = wrapper(foo)
foo()



"""
# @auth(chose) 相等于以下两行代码的解构
# wrapper = auth(chose)
# foo = wrapper(foo)
"""

2.多个装饰器装饰一个函数

def wrapper1(func):
    def inner1(*args,**kwargs):
        print(1)
        func(*args,**kwargs)
        print(11)
    return inner1

def wrapper2(func):  # func == foo
    def inner2(*args,**kwargs):
        print(11)
        func(*args, **kwargs)
        print(22)
    return inner2

def wrapper3(func):
    def inner3(*args,**kwargs):
        print(3)
        func(*args, **kwargs)
        print(33)
    return inner3

# @wrapper1  # 1 11
# @wrapper3  # 3 33
# @wrapper2  #  8 22

# def foo():
#     print(8)

# foo = wrapper2(foo)  # foo == inner2
# foo = wrapper3(foo)  # inner3 = wrapper3(inner2)
# foo = wrapper1(foo)  # inner1 = wrapper1(inner3)
# foo()                # inner1()


# foo = wrapper3(foo)  # foo == inner3
# foo = wrapper2(foo)  # foo = wrapper2(inner3)  foo == inner2
# foo = wrapper1(foo)  # foo = wrapper1(inner2)


被装饰的函数正上方有多个装饰器,先执行离被装饰函数最近的装饰器

3.今日总结

# 1.有参装饰器
# 在装饰器的基础上再套一层
# @auth("QQ")
# def foo():
#     pass
# f = auth("qq")
# foo = f(foo)
# foo()


# 2.多个装饰器装饰一个函数
# def wrapper1(func):
#     def inner1(*args,**kwargs):
#         print(1)
#         func(*args,**kwargs)
#         print(11)
#     return inner1
#
# def wrapper2(func):  # func == foo
#     def inner2(*args,**kwargs):
#         func(*args, **kwargs)
#         print(22)
#     return inner2
#
# def wrapper3(func):
#     def inner3(*args,**kwargs):
#         print(3)
#         func(*args, **kwargs)
#         print(33)
#     return inner3

# @wrapper1  # 1 11
# @wrapper3  # 3 33
# @wrapper2  #  8 22

# def foo():
#     print(8)

先执行离被装饰的函数最近的语法糖
小技巧:进入装饰器从上往下,走到最会一个装饰器执行被装饰的函数,退出装饰器从下往上走

3.今日练习

1.请实现一个装饰器，限制该函数被调用的频率，如10秒一次（面试题）
# import time
# def wrapper(f):
#     t = 0
#     def inner(*args,**kwargs):
#         nonlocal t
#         if time.time()-t >= 10:
#             t = time.time()
#             f(*args,**kwargs)
#         else:
#             print("被限制了")
#     return inner
# @wrapper
# def func():
#     print("被装饰函数")
# while True:
#     func()
#     time.sleep(2)
#     func()
#     time.sleep(2)
#     func()
#     time.sleep(2)
#
# 2.请写出下列代码片段的输出结果：
# def say_hi(func):
#     def wrapper(*args,**kwargs):
#         print("HI")
#         ret=func(*args,**kwargs)
#         print("BYE")
#         return ret
#     return wrapper
#
# def say_yo(func):
#     def wrapper(*args,**kwargs):
#         print("Yo")
#         return func(*args,**kwargs)
#     return wrapper
# @say_hi
# @say_yo
# def func():
#     print("ROCK&ROLL")
# func()
# HI
# Yo
# ROCK&ROLL
# BYE
#
3.编写装饰器完成下列需求:
# 用户有两套账号密码,一套为京东账号密码，一套为淘宝账号密码分别保存在两个文件中。
# 设置四个函数，分别代表 京东首页，京东超市，淘宝首页，淘宝超市。
# 启动程序后,呈现用户的选项为:
#   1,京东首页
#   2,京东超市
#   3,淘宝首页
#   4,淘宝超市
#   5,退出程序
# 四个函数都加上认证功能，用户可任意选择,用户选择京东超市或者京东首页,只要输入一次京东账号和密码并成功,
# 则这两个函数都可以任意访问;用户选择淘宝超市或者淘宝首页,只要输入一次淘宝账号和密码并成功,则这两个函数都可以任意访问.
# 相关提示：用带参数的装饰器。装饰器内部加入判断，验证不同的账户密码。
# msg = """
#   1,京东首页
#   2,京东超市
#   3,淘宝首页
#   4,淘宝超市
#   5,退出程序
#   请选择序号>>>:
# """
# login_dic = {
#     "jd":False,
#     "tb":False
# }
# def auth(argv):
#     def wrapper(f):
#         def inner(*args,**kwargs):
#             if login_dic[argv]:
#                 f(*args,**kwargs)
#             else:
#                 print(f"{argv} login")
#                 user = input("请输入姓名:")
#                 psd = input("请输入密码:")
#                 with open(argv,"r",encoding="utf-8") as f1:
#                     for i in f1:
#                         username,password = i.strip().split(":")
#                         if user == username and psd == password:
#                             login_dic[argv] = True
#                             print("登录成功!")
#                             return f(*args,**kwargs)
#                         else:
#                             print("账号或密码错误")
#                             return inner()
#         return inner
#     return wrapper
# 
# @auth("jd")
# def jd_index():
#     print("这是京东主页")
# 
# @auth("jd")
# def jd_shopping():
#     print("这是京东超市")
# 
# @auth("tb")
# def tb_index():
#     print("这是淘宝主页")
# 
# @auth("tb")
# def tb_shopping():
#     print("这是淘宝超市")
# 
# dic = {"1":jd_index ,"2":jd_shopping ,"3":tb_index,"4":tb_shopping, "5":exit}
# while True:
#     choose = input(msg)
#     if choose in dic:
#         dic[choose]()
#     else:
#         print("请正确输入")
#
4.给l1 = [1,1,2,2,3,3,6,6,5,5,2,2]去重，不能使用set集合（面试题）。
# l1 = [1,1,2,2,3,3,6,6,5,5,2,2]
# lst = []
# for i in l1:
#     if i not in lst:
#         lst.append(i)
# print(lst)
#
5.用递归函数完成斐波那契数列（面试题）：
# 斐波那契数列：1，1，2，3，5，8，13，21..........(第三个数为前两个数的和，但是最开始的1，1是特殊情况，可以单独讨论)
# lst = []
# def func(num):
#     if num == 0:
#         ret = 1
#     elif num == 1:
#         ret =1
#     else:
#         ret = (func(num-2)+func(num-1))
#     return ret
# num = int(input(">>>"))
# n = 0
# while func(n) < num:
#     lst.append(func(n))
#     n += 1
# print(lst)

6.用户输入序号获取对应的斐波那契数字：比如输入6，返回的结果为8.
# def func(num):
#     if num == 0:
#         ret = 1
#     elif num == 1:
#         ret =1
#     else:
#         ret = (func(num-2)+func(num-1))
#     return ret
# print(func(5))
7.请实现一个装饰器，限制该函数被调用的频率，如10秒一次（面试题）
# import time
# def wrapper(f):
#     t = 0
#     def inner(*args,**kwargs):
#         nonlocal t
#         if time.time()-t >= 10:
#             t = time.time()
#             f()
#         else:
#             print("被限制了")
#     return inner
# @wrapper
# def func():
#     print("被装饰函数")
# func()