在silverlight中实现Marquee效果

      今天在网上看到了这样一篇文章：
      Silverlight With Java Script Tutorial 12 - Silverlight Marquee Text
   
      教你实现Marquee效果，其主要代码是对StoryBoard的使用，本人在原文其中上又加了“向右，
向上，向下”滚动文字的效果（当然也可以滚动图片）。

      下面就是其演示效果(silverlight2 beta2):

src="http://silverlight.services.live.com/invoke/72193/marquee_sample/iframe.html" scrolling="no" frameborder="0" style="width:300px; height:300px">    
      其xaml代码如下:
   

< Canvas  xmlns ="http://schemas.microsoft.com/client/2007"   
           xmlns:x ="http://schemas.microsoft.com/winfx/2006/xaml" >
    < Canvas.Triggers >
        < EventTrigger  RoutedEvent ="Canvas.Loaded"   >
            < BeginStoryboard >
                < Storyboard  x:Name ="animation"  RepeatBehavior ="Forever"   >
                    < DoubleAnimation  Storyboard.TargetName ="ScrollingRight"
                   Storyboard.TargetProperty ="(Canvas.Left)"   From ="10"  To ="360"  Duration ="0:0:10"    />
                    < DoubleAnimation  Storyboard.TargetName ="ScrollingLeft"
                   Storyboard.TargetProperty ="(Canvas.Left)"  From ="360"  To ="-100"  Duration ="0:0:10"    />
                    < DoubleAnimation  Storyboard.TargetName ="ScrollingUp"
                   Storyboard.TargetProperty ="(Canvas.Top)"  From ="300"  To ="-60"  Duration ="0:0:10"    />
                    < DoubleAnimation  Storyboard.TargetName ="ScrollingDown"
                   Storyboard.TargetProperty ="(Canvas.Top)"  From ="-30"  To ="360"  Duration ="0:0:10"    />
                </ Storyboard >
            </ BeginStoryboard >
        </ EventTrigger >
    </ Canvas.Triggers >

    < TextBlock  x:Name ="ScrollingRight"  FontFamily ="Comic Sans MS"  FontSize ="36"  Foreground ="Green"  
                  Text ="向右"  Canvas.Top ="0"   />
    < TextBlock  x:Name ="ScrollingLeft"  FontFamily ="Comic Sans MS"  FontSize ="36"  Foreground ="Red"
                  Text ="向左"  Canvas.Top ="50" />      
    < TextBlock  x:Name ="ScrollingUp"  FontFamily ="Comic Sans MS"  FontSize ="36"  Foreground ="Blue"
                  Text ="向上"  Canvas.Left ="80"   />  
    < TextBlock  x:Name ="ScrollingDown"  FontFamily ="Comic Sans MS"  FontSize ="36"  Foreground ="Black"
                  Text ="向下"  Canvas.Left ="200"   />  
</ Canvas >