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UIElementBeginAnimation Method

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Starts an animation for a specified animated property on this element.

Namespace:   System.Windows
Assembly:  PresentationCore (in PresentationCore.dll)

public void BeginAnimation(
	DependencyProperty dp,
	AnimationTimeline animation
virtual void BeginAnimation(
	DependencyProperty^ dp,
	AnimationTimeline^ animation
) sealed
abstract BeginAnimation : 
        dp:DependencyProperty *
        animation:AnimationTimeline -> unit
override BeginAnimation : 
        dp:DependencyProperty *
        animation:AnimationTimeline -> unit
Public Sub BeginAnimation (
	dp As DependencyProperty,
	animation As AnimationTimeline



The property to animate, which is specified as a dependency property identifier.


The timeline of the animation to start.

When you check whether a property is animated, note that the animation will begin and be considered animated when the first frame beyond the non-animated starting point is rendered.

If the for animation is null, then any current animations are removed and the current value of the property is held.

If the entire animation value is null, all animations are removed from the property and the property value reverts to its base value. However, the originally associated animation timeline is not stopped. Any other animations assigned to that timeline will continue to run.

The following example creates an animation, assigns it, and then calls BeginAnimation to start it.

// Animate the button's width.
DoubleAnimation widthAnimation = 
    new DoubleAnimation(120, 300, TimeSpan.FromSeconds(5));
widthAnimation.RepeatBehavior = RepeatBehavior.Forever;
widthAnimation.AutoReverse = true;
animatedButton.BeginAnimation(Button.WidthProperty, widthAnimation);
' Animate the button's width.
Dim widthAnimation As New DoubleAnimation(120, 300, TimeSpan.FromSeconds(5))
widthAnimation.RepeatBehavior = RepeatBehavior.Forever
widthAnimation.AutoReverse = True
animatedButton.BeginAnimation(Button.WidthProperty, widthAnimation)
.NET Framework
Available since 3.0
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