<Window x:Class="WpfApplication1.ShapesWindow" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Title="ShapesWindow" Height="160" Width="400"> <StackPanel Orientation="Horizontal"> <Polygon Fill="Red" Canvas.Left = "100" Canvas.Top="30" Points="20 0 40 40 0 40" MouseDown="Polygon_MouseDown"/> </StackPanel> </Window> //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.Shapes; namespace WpfApplication1 { public partial class ShapesWindow : Window { public ShapesWindow() { InitializeComponent(); } private void Polygon_MouseDown(object sender, MouseButtonEventArgs e) { MessageBox.Show("Hi"); } } }