private void registBtn_Click(object sender, RoutedEventArgs e)
 {
     if (userName.Text == "" || userPasswd.Text == "" || userNickName.Text == "")
     {
         MessageBox.Show("用户名、密码、昵称不可为空!", "message", MessageBoxButton.OK);
     }
     else
     {
         AccessHelper.RegistUser(userName.Text, userPasswd.Text, userNickName.Text, userPhone.Text, userQQ.Text, userEmail.Text, userAddress.Text);
         this.Close();
     }
 }