190327 Python登录接口

 #！Author:John
 # _*_ coding: utf-8 _*_
 #编写登录接口
 #输入用户名密码
 #认证成功后显示欢迎信息
 #输错三次后锁定
 import sys, os, getpass

 limit = 3
 count = 0
 account_file = "account.txt"
 lock_file = "locked.txt"

 while count < limit:
     username = input("Please input username:")
     # 打开文件后第一步输入用户名，打开lock文件，检查改用户是否已经被锁定

     f1 = open(lock_file,'r')
     # r后面不能加b，加b是以bytes类型打开，输入的用户名、密码是字符串str和bytes不匹配
     for line in f1.readlines():
         if username == line.strip():
             sys.exit("User %s has been locked!"%username)
     f1.close()
     password = input("Please input password:")

     f = open(account_file, 'r')
     match_flag = False
     for line in f.readlines():
         user,pwd=line.strip().split()   # 这里的知识点需要掌握
         if user==username and pwd == password:
             print(username,"has match successfully!")
             match_flag=True
             break
     f.close()
     if match_flag==False:
         print("Username or password is incorrect!")
         count+=1
     else:
         print("Welcome login Python Learning system!")
         break
 else:
     print("Your account has been locked!")
     f1=open(lock_file,"a")
     f1.write(username+'\n')
     f1.close()