学习python第一次应用---编写登录接口（关于while、if、for语句，dict以及文件的读写）

  第一天看完python教学视频后，马上写了一小段代码，中间遇到了一些问题，想要马上记录下来，跟大家分享。

编写登陆接口

• 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

1.使用dict进行读写文件（因为想用key，value的结构）：1）使用dict的格式写入文件中：

userfile = open("C:/Users/Administrator/PycharmProjects/untitled/day1/userdata.ini","w")

temp = {}temp[‘name‘] = "shelly"temp[‘passwd‘] = "123456"userfile.write(str(temp)+ ‘\n‘)temp[‘name‘] = "Nancy"temp[‘passwd‘] = "234567"userfile.write(str(temp) + ‘\n‘)userfile.close()

2）使用dict的格式从文件中读取出来：

userfile = open("C:/Users/Administrator/PycharmProjects/untitled/day1/userdata.ini", "r")lines = userfile.readlines()for line in lines:    data = eval(line)     verifyData = False    if data[‘name‘] == username and data[‘passwd‘] == passwd:       print("welcome {_name} login ".format(_name = username))       userfile.close()       exit()

1.按行读取：我将被锁定的名字记录到文件时，换行了，结果在匹配用户输入的名字，是否是被锁定的用户名，按行读取文件，进行匹配时，发现读取出来的值有换行符，导致判断有问题。直接按行读取出来的数值会变成：shelly\n解决方法：

data = line.split()[0]这样读取出来的数据就会可以转化成想要的：shelly了。

我写的代码如下：

#coding=utf-8import oscount = 3while count > 0:    username = input("please input username:")    lockFile = open("C:/Users/Administrator/PycharmProjects/untitled/day1/lockList.cfg", "r")    lines = lockFile.readlines()    for line in lines:        if username == line.split()[0]:            print("Account is locked!!! ")            exit();    lockFile.close()    passwd = input("please input your passworld:")    userfile = open("C:/Users/Administrator/PycharmProjects/untitled/day1/userdata.ini", "r")    lines = userfile.readlines()    for line in lines:        data = eval(line)        verifyData = False        if data[‘name‘] == username and data[‘passwd‘] == passwd:            print("welcome {_name} login ".format(_name = username))            userfile.close()            exit()    count -= 1    if count > 0:        print("Your username or passworld is wrong!only have {_count} chance".format(_count = count))    else:        lockFile = open("C:/Users/Administrator/PycharmProjects/untitled/day1/lockLiat.cfg", "a")        lockFile.write(username+"\n")        lockFile.close()        print("Sorry,You have no chance!")    userfile.close()

原文地址：https://www.cnblogs.com/malimali/p/9175441.html