Python学习————作业

1、编写文件修改功能，调用函数时，传入三个参数（修改的文件路径，要修改的内容，修改后的内容）既可完成文件的修改

2、编写tail工具

def tail(x):
    with open(x, mode='rt', encoding='utf-8') as f:
        for i in f:
            print('原文件：', i)
            print('新文件：')
        while True:
            res = f.readline()
            if len(res) == 0:
                continue
            else:
                print(res)


tail('x.txt')

3、编写注册登录功能

def user_register():
    print('注 册')
    user = input('请输入帐号： ')
    password = input('请输入密码：')
    with open(r'userlist.txt', mode='at', encoding='utf-8') as f:
        f.write(f'{user}:{password:}
')


user_register()


def login():
    print('登 录')
    userinfo = input('请输入帐号： ')
    pwd= input('请输入密码：')
    with open(r'userlist.txt', 'r', encoding='utf-8') as f:
        for line in f:
            username, password = line.strip().split(":")
            if username == userinfo and pwd == password:
                print("登录成功")
                break
        else:
            print("输入错误")


login()