路飞学城14天集训营作业1—登陆认证

作业一：登陆认证基础需求：
让用户输入用户名密码
认证成功后显示欢迎信息
输错三次后退出程序

升级需求：
可以支持多个用户登录 (提示，通过列表存多个账户信息)
用户3次认证失败后，退出程序，再次启动程序尝试登录时，还是锁定状态（提示:需把用户锁定的状态存到文件里）

初始版本：

 1 # -*- coding:utf-8 -*-
 2 # author: heimu
 3
 4 import os
 5
 6 user_dic = {"heimu_1":"111111","heimu_2":"222222","heimu_3":"333333"}
 7 lock_state = []
 8 count = 1
 9 if os.path.isfile("lock_state.txt"):
10     with open("lock_state.txt","r") as f:
11         lock_state = f.readline()
12 while count <= 3:
13     user_name_input = input("please input user name: ")
14     passwords_input = input("please input six digital passwords: ")
15     if user_name_input in lock_state:
16         print("Sorry,%s account has been locked" % user_name_input)
17         break
18     elif user_name_input in user_dic and user_dic[user_name_input] == passwords_input:
19         print("Welcome!%s" % user_name_input)
20         break
21     elif count < 3:
22         print("Authentication failure! Please input again.")
23     else:
24         print("You have failed three times,the program is going to exit !!!")
25         if user_name_input in user_dic:
26             with open("lock_state.txt","a") as f:
27                 f.write(user_name_input)
28     count+=1

经过大王的悉心教诲之后的版本

 1 # -*- coding:utf-8 -*-
 2 # author: heimu
 3
 4 import os
 5
 6 user_dic = {"heimu_1":"111111","heimu_2":"222222","heimu_3":"333333"}
 7 lock_state = []         # 存储黑名单
 8 count = 1
 9 first_input_user = None     # 记录第一次输入的账户名
10 is_same_user = True         # 标志位，用于判断三次输入的用户名是否相同
11
12 if os.path.isfile("lock_state.txt"):        # 如果文件存在则打开文件
13     with open("lock_state.txt","r") as f:   # 使用with语句，省去了每次得手动关闭文件
14         for line in f:                      # 迭代f文件，line循环一次表示一行
15             lock_state.append(line.strip()) # .strip 表示取出空格换行符之类的
16
17 # 主函数
18 while count <= 3:
19     user_name_input = input("please input user name: ")
20     passwords_input = input("please input six digital passwords: ")
21     if user_name_input in lock_state:       # 如果账户存在于黑名单，直接退出
22         exit("Sorry,%s account has been locked" % user_name_input)
23     if not first_input_user:                # 如果为None，代表为第一次输入账户
24         first_input_user = user_name_input
25     if first_input_user != user_name_input: # 代表本次输入的用户名和第一次用户名不一样
26         is_same_user = False                # 标志位设置为False，表示不再执行账户锁定操作
27     if user_name_input in user_dic and user_dic[user_name_input] == passwords_input:
28         print("Welcome!%s" % user_name_input)   # 登陆成功
29         break
30     else:
31         print("Authentication failure! Please input again.")    # 失败错误少于三次，打印认证失败语句
32     count+=1
33 else:
34     print("You have failed three times,the program is going to exit !!!")
35     if is_same_user:        # 锁定用户
36         if user_name_input in user_dic:     # 如果账户名存在于文件中，把账户名加入黑名单
37             print("%s账户已经锁定" % user_name_input)
38             with open("lock_state.txt","a") as f:
39                 f.write(user_name_input+‘\n‘)
40         else:
41             pass                            # 如果账户名不在文件中，就算重复三次也不加入黑名单

原文地址：https://www.cnblogs.com/heimu24/p/8541360.html