登录界面

while 1:
    username =input ('请输入你的注册账号：')
    userkey = input('请输入你的注册密码(只能是纯数字)：')
    if userkey.isdigit():
        with open('数据存储','r+',encoding='utf-8') as f:
            f.write('{} \n {}'.format(username,userkey))
        print("注册成功")
        break
    else:
        print('请输入数字')
i = []
l = 0
while l < 3:
    user = input('请输入账号：')
    key1 = input('请输入密码：')
    with open('数据存储','r+',encoding='utf-8') as f:
            for line in  f:
                i.append(line)
                print(i)
                if user == i[0].strip() and key1 == i[1].strip():
                        print("登录成功")
                        break
                else:
                    print('登陆失败')
                    print('你还有{}次机会'.format(l))
                l += 1

这个代码有问题，嗯.

不知为何，usrkey不能添加进入列表

待修改

修改完成

原因：将if循环列入了for循环中，导致每次只输入一个元素进入列表中

while 1:
    username =input ('请输入你的注册账号：')
    userkey = input('请输入你的注册密码(只能是纯数字)：')
    if userkey.isdigit():
        with open('数据存储','r+',encoding='utf-8') as f:
            f.write('{} \n {}'.format(username,userkey))
        print("注册成功")
        break
    else:
        print('请输入数字')
i = []
l = 0
while l < 3:
    user = input('请输入账号：')
    key1 = input('请输入密码：')
    with open('数据存储','r+',encoding='utf-8') as f:
            for yihang in  f:
                i.append(yihang)
                print(i)
    if user == i[0].strip() and key1 == i[1].strip():
            print("登录成功")
            break
    else:
                print('登陆失败')
                print('你还有{}次机会'.format(l))
                l += 1