SL21: Replacing A Silverlight Timed Animation With a Nonanimated Element

<UserControl x:Class="StopAnimation.MainPage"
   xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
   xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:sys="clr-namespace:System;assembly=mscorlib">
   <UserControl.Resources>
       <ImageBrush x:Key="Stars" ImageSource="/stars.jpg" Stretch="Fill"/>
       <Storyboard x:Key="crawl">
           <DoubleAnimation From="700" To="-100" Duration="0:0:20"
             Storyboard.TargetName="crawltext" Storyboard.TargetProperty="(Canvas.Top)"/> 
       </Storyboard>
       <sys:String x:Key="crawlText">
           Episode IV, A NEW HOPE It is a period of civil war. Rebel spaceships, striking from a hidden base, 
           have won their first victory against the evil Galactic Empire. During the battle, Rebel spies managed 
           to steal secret plans to the Empire’s ultimate weapon, the DEATH STAR, an armored space station with 
           enough power to destroy an entire planet. Pursued by the Empire’s sinister agents, Princess Leia 
           races home aboard her starship, custodian of the stolen plans that can save her people and restore 
           freedom to the galaxy….
       </sys:String>
   </UserControl.Resources>
   <StackPanel x:Name="LayoutRoot"
   Background="{StaticResource Stars}"
   Height="600" Width="800">
       <Button Width="200"
   Click="Button_Click">Stop crawling text, display fixed text</Button>
       <Canvas Name="CrawlPanel" Width="605" Height="595" >
           <Canvas.Projection>
               <PlaneProjection RotationX="-75"/>
           </Canvas.Projection>
           <Canvas.Clip>
               <RectangleGeometry Rect="0 0 600 600"/>
           </Canvas.Clip>
           <TextBlock Text="{StaticResource crawlText}"
   TextWrapping="Wrap" FontSize="20"
   Width="300" Canvas.Left="150" Name="crawltext"
   Foreground="Goldenrod"/>
       </Canvas>
   </StackPanel>
</UserControl>

       public MainPage()
       {
           InitializeComponent();
           (this.Resources["crawl"] as Storyboard).Begin();
       }
       private void Button_Click(object sender, RoutedEventArgs e)
       {
           (this.Resources["crawl"] as Storyboard).Stop();
           LayoutRoot.Children.Remove(CrawlPanel);
           TextBox tb = new TextBox();
           tb.IsReadOnly = true;
           tb.FontSize = 30;
           tb.TextWrapping = TextWrapping.Wrap;
           tb.Text = (string)this.Resources["crawlText"];
           LayoutRoot.Children.Add(tb);
       }