Use Mouse.AddPreviewMouseDownHandler(myEllipse, PreviewMouseDownEllipse);


   
  

<Window x:Class="WpfApplication1.AttachedEvents"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="Event Examples" Height="300" Width="300">
  <Grid HorizontalAlignment="Center" VerticalAlignment="Center">
    <Button>
      <Grid>
        <Grid.ColumnDefinitions>
          <ColumnDefinition />
          <ColumnDefinition />
        </Grid.ColumnDefinitions>

          <Ellipse x:Name="myEllipse" Canvas.Left="1" Canvas.Top="1" Width="16" Height="16" Fill="Yellow" Stroke="Black" />

          <Ellipse Canvas.Left="4.5" Canvas.Top="5" Width="2.5" Height="3" Fill="Black" />
          <Ellipse Canvas.Left="11" Canvas.Top="5" Width="2.5" Height="3" Fill="Black" />
          <Path Data="M 5,10 A 3,3 0 0 0 13,10" Stroke="Black" />
      
        <TextBlock Grid.Column="1">Click!</TextBlock>
      </Grid>
    </Button>
  </Grid>
</Window>

//File:Window.xaml.cs

using System;
using System.Windows;
using System.Diagnostics;
using System.Windows.Shapes;
using System.Windows.Input;

namespace WpfApplication1
{
    public partial class AttachedEvents : System.Windows.Window
    {

        public AttachedEvents()
        {
            InitializeComponent();

            Mouse.AddPreviewMouseDownHandler(myEllipse, PreviewMouseDownEllipse);
            Mouse.AddMouseDownHandler(myEllipse, MouseDownEllipse);

        }

        void PreviewMouseDownEllipse(object sender, RoutedEventArgs e)
        { Debug.WriteLine("PreviewMouseDownEllipse"); }

        void MouseDownEllipse(object sender, RoutedEventArgs e)
        { Debug.WriteLine("MouseDownEllipse"); }

    }
}