停止动画并使用开关案例启动另一个动画

Question

我有这个动画，它在加载时开始：

<Grid.Triggers>
        <EventTrigger RoutedEvent= "Canvas.Loaded">
            <BeginStoryboard>
                <Storyboard x:Name="sb1" RepeatBehavior="Forever">
                    <DoubleAnimation Name="earth" From="0" To="-360" Duration="0:0:10" AutoReverse="False" Storyboard.TargetName="rotation" Storyboard.TargetProperty="Angle" />
                </Storyboard>
            </BeginStoryboard>
        </EventTrigger>           
    </Grid.Triggers>

如何停止此操作并使用我的开关案例（如鼠标悬停）输入另一个事件触发器。 我正在使用kinect音频源，因此当用户说“美国”或“欧洲”时，动画应该停留在该大陆。

<EventTrigger RoutedEvent= ""><!--switch case "AMERICA" -->
            <BeginStoryboard>
                <Storyboard x:Name="sb2">
                    <DoubleAnimation Name="america" To="0" Duration="0:0:5" AutoReverse="False" Storyboard.TargetName="rotation" Storyboard.TargetProperty="Angle" />
                </Storyboard>
            </BeginStoryboard>
        </EventTrigger>      

我试过这个，但不起作用：

 switch (e.Result.Semantics.Value.ToString())
            {

                case "AMERICA":
                    americaSpan.Foreground = Brushes.DeepSkyBlue;
                    americaSpan.FontWeight = FontWeights.Bold;

                    Storyboard storyBoard1 = (Storyboard)FindName("sb1");
                    Storyboard storyBoard2 = (Storyboard)FindName("sb2");
                    storyBoard1.Stop();
                    storyBoard2.Begin();

                    break;   

            }