要是想实现，点击后换成另外一个图片不变，还应该怎么办？
<Window x:Class="WpfApplication2.MainWindow"
  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
  Title="MainWindow" Height="350" Width="525">
  <Window.Resources>

  <ControlTemplate x:Key="IconButton" TargetType="{x:Type Button}">

  <Grid >

  <Image x:Name="myimage" Source="c:\users\candy\documents\visual studio 2010\Projects\WpfApplication2\WpfApplication2\Images\1.jpg" Height="27" Width="65" />

  <Border>

  <ContentPresenter Content="{TemplateBinding Content}"/>

  </Border>

  </Grid>

  <ControlTemplate.Triggers >

  <Trigger Property="IsMouseOver" Value="True">

  <Setter TargetName="myimage" Property="Source" Value="c:\users\candy\documents\visual studio 2010\Projects\WpfApplication2\WpfApplication2\Images\2.jpg" />

  </Trigger>

  </ControlTemplate.Triggers>

  </ControlTemplate>

  </Window.Resources>

  <Button Width="50" Height="30" Template="{StaticResource IconButton}" Margin="15" HorizontalAlignment="Left" x:Name="Start" ToolTip="Start measurement">

   

  </Button>

</Window>

------解决方案--------------------
<ControlTemplate.Triggers>
<DataTrigger Binding="{Binding Path=S}" Value="1">
<Setter TargetName="rectangle" Property="Fill">
<Setter.Value>
<ImageBrush ImageSource="c:\users\candy\documents\visual studio 2010\Projects\WpfApplication2\WpfApplication2\Images\2.jpg" ></ImageBrush>
</Setter.Value>
</Setter>
</DataTrigger>
</ControlTemplate.Triggers>
用类似于这样的后台绑定一个数据的方法