*　　用戶登錄模塊

給定用戶信息表,需要滿足條件如下:

1. 輸入用戶名密碼判斷

2. 輸入錯誤次數3次時,詢問用戶是否需要繼續嘗試,Y繼續,N結束

3. 可支持多用戶登錄

 1 # 方案一:輸入用戶名後立即判斷一次,共三次
 2 li = [{‘username‘: ‘qqq‘, ‘password‘: ‘www‘},
 3       {‘username‘: ‘aaa‘, ‘password‘: ‘sss‘},
 4       {‘username‘: ‘zzz‘, ‘password‘: ‘xxx‘}]
 5 
 6 # 將原列表轉換為方便比較的新字典
 7 new_users_info = {}
 
 8 for i in li:
 9     new_users_info[i[‘username‘]] = i[‘password‘]
10 
11 count_try_username, count_try_password = 0, 0  # 用戶名嘗試次數,密碼嘗試次數
12 flag_username, flag_password, flag_selection = 1, 1, 1  # 循環到用戶名輸入,循環到密碼輸入,循環到是否繼續
13 while flag_username:
14     count_try_username += 1
15     username_input = input(‘
 
請輸入用戶名:‘)
16     if username_input in new_users_info.keys():  # 判斷用戶名是否存在
17         count_try_password = 0  # 用戶名嘗試次數歸零/或歸1
18         flag_password, flag_selection = 1, 1  # 所有循環重新開始
19         while flag_password:
20             password_input = input(‘請輸入密碼:‘)
21             if password_input == new_users_info[username_input]:  #
 
 判斷密碼是否與用戶名匹配
22                 print(‘登錄成功!跳轉到APP使用頁面‘)
23                 flag_username = 0
24                 break
25             else:
26                 count_try_password += 1
27                 print(‘密碼輸入錯誤...%s次‘ % count_try_password)
28                 if count_try_password == 3:
29                     while flag_selection:
30                         user_selection = input(‘是否繼續?Y/N‘)
31                         user_selection = user_selection.lower()
32                         if user_selection == ‘y‘:
33                             count_try_username, count_try_password = 0, 0
34                             flag_password = 0
35                             flag_selection = 0
36                         elif user_selection == ‘n‘:
37                             flag_username = 0
38                             flag_password, flag_selection = 0, 0
39                             print(‘ByeBye...‘)
40                         else:
41                             print(‘錯誤選擇‘)
42     else:
43         print(‘用戶名輸入錯誤...%s次‘ % count_try_username)
44         if count_try_username == 3:
45             flag_password, flag_selection = 1, 1  # 所有循環重新開始
46             while flag_selection:
47                 user_selection = input(‘是否繼續?Y/N‘)
48                 user_selection = user_selection.lower()
49                 if user_selection == ‘y‘:
50                     count_try_username = 0
51                     flag_password = 0
52                     flag_selection = 0
53                 elif user_selection == ‘n‘:
54                     flag_username = 0
55                     flag_password, flag_selection = 0, 0
56                     print(‘ByeBye...‘)
57                 else:
58                     print(‘錯誤選擇‘)

以上代碼會判斷用戶名錯誤三次的情況.

以下代碼不判斷用戶名錯誤,只判斷匹配.

 1 # 用戶登錄(三次機會重試),可以支持多用戶登錄,三次後可選擇Y/N決定是否繼續嘗試
 2 # 方案二:不判斷用戶名錯誤次數,只判斷密碼是否錯誤
 3 li = [{‘username‘: ‘li_alex‘, ‘password‘: ‘SB‘},
 4       {‘username‘: ‘wu_sir‘, ‘password‘: ‘sb‘},
 5       {‘username‘: ‘xu_jin‘, ‘password‘: ‘student‘}]
 6 
 7 new_user_info = {}
 8 for user_info in li:
 9     new_user_info[user_info[‘username‘]] = user_info[‘password‘]
10 print(new_user_info)
11 
12 while 1:
13     count = 0
14     username_entry = input(‘Please Input an Username: ‘)
15     if username_entry in new_user_info.keys():
16         password_entry = input(‘Please Input the Password: ‘)
17         while count < 2 and password_entry != new_user_info[username_entry]:
18             count += 1
19             print(‘Wrong Password Input, %d time(s) left...‘ % (3 - count))
20             password_entry = input(‘Please Input the Password: ‘)
21         else:
22             if password_entry == new_user_info[username_entry]:
23                 print(‘Congratulations! Login Succeed!‘)
24                 break
25             elif count > 1:
26                 user_selection = input(‘Invalid time Exceeds Limited, Do You Wanna Try Again? Y/N ‘)
27                 lower_entry = user_selection.lower()
28                 if lower_entry == ‘y‘:
29                     continue
30                 elif lower_entry == ‘n‘:
31                     print(‘You Give up Login attempt. Good luck...(手動微笑)‘)
32                     break
33                 else:
34                     print(‘Wrong Selection...Please Try Again...‘)
35                     continue
36             else:
37                 print("error")

均不使用函數等方法,只用while/for/if-else循環

python用戶登錄模塊(不使用函數等方法)