Python之簡單的用戶登錄和注冊

#!/bin/bash/env python
# -*- coding:utf-8 -*-

def login(username,password):
    """
    用於用戶名密碼的登錄
    :param username: 用戶名
    :param password:  密碼
    :return:  True，用戶驗證成功；False，驗證失敗
    """
    with open('cai.log','r',encoding="utf-8") as f:
        for line in f:      #一行一行的讀取
            line = line.strip()     #去除兩端的空格及換行符
            line_list = line.split("$")     #以$符號進行分割
            if username == line_list[0] and password == line_list[1]:
                return True
    return False

def register(username,password):
    """
    注冊用戶
    :param username: 用戶名
    :param password: 密碼
    :return: True，注冊成功
    """
    with open('cai.log',"a",encoding="utf-8") as f:
        temp = "\n" + username + "$" +password
        f.write(temp)
    return True

def user_exist(username):
    """
    檢查用戶是否已經存在
    :param username: 用戶名
    :return: True，則用戶名已經存在；False，用戶名不存在
    """
    with open('cai.log',"r",encoding="utf-8") as f:
        for line in f:
            line = line.strip()
            line_list = line.split("$")
            if username == line_list[0]:
                return True
    return False

def main():
    print("歡迎登陸瑞的系統")
    inp = input("1: 登陸;2: 注冊")

    user = input("請輸入用戶名：")
    pwd = input("請輸入密碼：")

    if inp == "1":
        is_login = login(user,pwd)
        if is_login:
            print("登錄成功")
        else:
            print("登錄失敗")
    elif inp == "2":
        is_exist = user_exist(user)
        if is_exist:
            print("用戶已經存在，無法注冊")
        else:
            result = register(user,pwd)
            if result:
                print("注冊成功")
            else:
                print("注冊失敗")

main()