Storyboard Animation in Expression Blend and Code Behind

Hey!

I have a specific problem concerning storyboard animations in Expression Blend and Visual Studio. I already searched through the web for solutions, but since I am still a beginner, I find it hard to adapt the found solutions to my problem.

I created a storyboard animation in Expression Blend, here is the xaml- code:

<Storyboard x:Key="okHaken"><DoubleAnimationUsingKeyFrames Storyboard.TargetProperty="(UIElement.Opacity)" Storyboard.TargetName="image"><EasingDoubleKeyFrame KeyTime="0:0:0.5" Value="1"/><EasingDoubleKeyFrame KeyTime="0:0:1" Value="1"/><EasingDoubleKeyFrame KeyTime="0:0:1.5" Value="1"/></DoubleAnimationUsingKeyFrames></Storyboard></Window.Resources><Window.Triggers><EventTrigger RoutedEvent="ButtonBase.Click" SourceName="hinzu_btHinzu"><BeginStoryboard x:Name="okHaken_BeginStoryboard" Storyboard="{StaticResource okHaken}"/></EventTrigger></Window.Triggers>

As you can see, I am triggering the animation with the button click event. What I do then is check trough the input in of my text boxes and verify it. If they are OK, the animation can be seen. However, if the input is not OK, the animation finishes anyway. And I want to stop the animation in the button.clicked- event, if the input is wrong.

How do I do that?