Ajax (4) ajaxToolkit:UpdatePanelAnimationExtender

<ajaxToolkit:UpdatePanelAnimationExtender runat="server"

ID="Animation1" TargetControlID="UpdatePanel2">

<Animations>

<OnUpdating>

<Color AnimationTarget="list" PropertyKey="backgroundColor"

Duration="0.5" Fps="30" StartValue="#FFFFFF" EndValue="#00EEEE"></Color>

</OnUpdating>

<OnUpdated>

<Color AnimationTarget="list" PropertyKey="backgroundColor"

Duration="0.5" Fps="30" EndValue="#FFFFFF" StartValue="#00EEEE"></Color>

</OnUpdated>

</Animations>

</ajaxToolkit:UpdatePanelAnimationExtender>