Python 基础

_{作业要求：}

1. 用户输入帐号密码进行登陆

2. 用户信息保存在文件内

3. 用户密码输入错误三次后锁定用户

知识点总结：

1. file的操作： with open 

2. 读取file信息， 从string 转为 list  

3. 读取file信息， 从string 转为list, 专为字典 (此处注意，是一一添加的）

4. 字符串格式化输出 （%） ： % user_name, psw               注意没有parenthese

5. 最后须仔细测试，同时调整代码逻辑及格式。 

_{MY WORK}

#!usr/bin/env python
# -*- coding:utf-8 -*-
# Author: Jane Yue

import sys


locked_list = []                                                    # 题点：将file信息 读到 List里
with open('locked_file', 'r+') as f:
    for line in f.readlines():
        locked_list.append(line.strip())                            # print返回值：['BigHead']


user_info = {}
with open('user_info', 'r+') as f:
    for line in f.readlines():
        user_list = line.strip().split()                            # 题点：将string变3个list
        user_info[user_list[0]] = user_list[1]                      # 题点：将 list加到 dictionary


def login():                                                        # 定义 login 函数
    count = 3
    while count >= 0:
        psw = input('Password: ')                                   # 输入password
        if psw == user_info.get(user_name):
            print('Welcome to login, %s' % user_name)
            sys.exit()
        else:
            count -= 1
            if count > 0:
                print("Login incorrect. You can try another %d times" % count)
                continue
            else:
                print('You account has been blocked. Please contact the administrator')
                with open('locked_file', 'a') as f1:
                    f1.write("
%s" % user_name)
                sys.exit()

while True:
    user_name = input('Username: ')                                     # 主程序
    if user_name in user_info.keys():
        if user_name in locked_list:
            print('Your account has been blocked, please contact the administrator')
        else:
            login()
    else:
        print('Username does not exist')
        continue 

_{SAMPLE 1: By 刘}

步骤：

1. 字符串读取转成字典

user_info = 'Eric:123456#Catherine:098765'
user_list = user_info.split('#')
print(user_list)

user_dic ={}      # 创建空字典
for item in user_list:
    item_list = item.split(':')  # >>> ['eric','123456',''Catherine','098765']
    user_dic[item_list[0]] = item_list[-1]   #？？？
print(user_dic)

 {'Eric': '123456', 'Catherine': '098765'}

2. 从文件中读取字符串

f = open('user_info.txt','r')
user_info = f.read()
f.close()

user_list = user_info.split('#')
print(user_list)

user_dic ={}      # 创建空字典
for item in user_list:
    item_list = item.split(':')  # >>> ['eric','123456',''Catherine','098765']
    user_dic[item_list[0]] = item_list[-1]   #
print(user_dic)

3. 程序的主要部分

import sys

user_info = {'alex': "123",'wenwei': 'gdalex'}

count = 0
username = input('用户名 >>> : ')
if username in user_info:
    # lock_list = 读取锁定文件的信息
    lock_list = ['alex']
    if user_info in lock_list:
        print('被锁定')
        sys.exit()
    else:
        while count < 3:
            password = input('pwd >>>:')
            if password == user_info[username]:
                print('登陆成功，欢迎%s' % username)
                sys.exit()
            else:
                count += 1
                if count == 3:
                    print('被说点，请联系管理员')
                    sys.exit()
                else:
                    print('密码错误！请重新输入。还有%s次机会' % (3-count))
else:
    print('用户名不存在')

 MY WORK: