xaml：
 <Rectangle>            <Rectangle.RenderTransform>                <TranslateTransform x:Name="myTranslateTransform" />            </Rectangle.RenderTransform> </Rectangle>

cs:

myTranslateTransform.X = myTranslateTransform.X + 15;myTranslateTransform.Y = myTranslateTransform.Y + 15;

http://msdn.microsoft.com/en-us/library/windows/apps/system.windows.media.translatetransform%28v=vs.105%29.aspx