wpf 帧动画

<ImageBrush x:Key="speed_s" Stretch="Fill" ImageSource="/images/air/speed_s.png" />
        <ImageBrush x:Key="speed_m" ImageSource="/images/air/speed_m.png" />
        <ImageBrush x:Key="speed_l" ImageSource="/images/air/speed_l.png" />

<Storyboard x:Name="FrameAnim">
            <ObjectAnimationUsingKeyFrames Duration="0:0:1.6" RepeatBehavior="Forever" Storyboard.TargetName="WindSpeedThumb" Storyboard.TargetProperty="Fill">
                <DiscreteObjectKeyFrame KeyTime="0:0:0.4" Value="{StaticResource speed_s}" />
                <DiscreteObjectKeyFrame KeyTime="0:0:0.8" Value="{StaticResource speed_m}" />
                <DiscreteObjectKeyFrame KeyTime="0:0:1.2" Value="{StaticResource speed_l}" />
            </ObjectAnimationUsingKeyFrames>
        </Storyboard>


 <Grid Margin="0,0,28,40" Width="98" Height="98" HorizontalAlignment="Right" VerticalAlignment="Bottom">
                <!--<Image Width="35" Margin="0,10,0,0" Stretch="Uniform" VerticalAlignment="Top" Source="/images/air/direction_0.png" />-->
                <Rectangle x:Name="WindDirectionThumb" Width="35" Height="35" Margin="0,10,0,0" VerticalAlignment="Top" Fill="{StaticResource direction_0}" />
                <pretty:PrettyButton x:Name="WindDirection" Margin="0,0,0,-7" Width="97" Height="55" VerticalAlignment="Bottom" PressedBrush="{StaticResource ac_winddirection_s}" NormalBrush="{StaticResource ac_winddirection_d}" />
            </Grid>

 FrameAnim.Begin();


FrameAnim.Stop();