private void Btn_Login_Click(object sender, EventArgs e) { var username = Tb_UserName.Text; var password = Tb_Password.Text; var user = new RegisterUser(); var currentUser = user.GetCurrentUser(username); var pswd = user.encodePassword(password); if (currentUser.Username.Equals(username) && currentUser.Password.Equals(pswd)) { var main = new Main(username, Configuration); main.ShowDialog(); } else { MessageBox.Show("Benutzername oder Password falsch!", "", MessageBoxButtons.OK, MessageBoxIcon.Hand); } }