CODE EXAMPLE FOR CSHARP

wpf yes no message box exit

var response = MessageBox.Show("Do you really want to exit?", "Exiting...",
                                      MessageBoxButton.YesNo, MessageBoxImage.Exclamation);
            if (response == MessageBoxResult.No)
            {
                e.Cancel = true;
            }
            else
            {
                Environment.Exit(0);
            }