这种事情就像 prohibited 一样，这就是为什么要创建OAuth或OpenID之类的原因.这类事情使用户无需输入用户名和密码即可登录.所以要小心.

This kind of things are like prohibited, that's why things like OAuth or OpenID are created. This kind of things permit the user to login without entering username and password. So be careful.