private void btnLogin_Click(object sender, RoutedEventArgs e) { view = new LoginView(); string email = txtUsername.Text; string pass = txtPassword.Text; if (txtPassword.Text != "" && txtUsername.Text != "") { if (view.getData(email, pass) != null) { this.Frame.Navigate(typeof(InstitutionPage)); } else { messageBox("You have entered wrong password"); } } else { messageBox("please enter values"); } }