//File:Window.xaml.cs using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Windows; using System.Windows.Controls; using System.Windows.Data; using System.Windows.Documents; using System.Windows.Input; using System.Windows.Media; using System.Windows.Media.Imaging; using System.Windows.Navigation; using System.Windows.Shapes; namespace WpfApplication1 { public partial class Window1 : Window { public Window1() { InitializeComponent(); } private void button1_Click(object sender, RoutedEventArgs e) { MessageBox.Show("Please don’t click this button again"); } } }