如何：重复动画
此示例演示如何使用 Timeline 的 RepeatBehavior 属性控制动画的重复行为。
示例
Timeline 的 RepeatBehavior 属性控制动画重复其简单期间的次数。 通过使用 RepeatBehavior，您可以指定让 Timeline 重复一定的次数（重复次数）或在指定的一段时间内发生重复。 无论是哪一种情况，动画都将从头到尾地不断运行，直到完成要求的次数或经历完所需的一段时间。
默认情况下，时间线的重复次数为 1.0，即播放一次时间线，不进行重复。 但是，如果将 Timeline 的 RepeatBehavior 属性设置为 Forever，则时间线将会无限重复。
下面的示例演示如何使用 RepeatBehavior 属性控制动画的重复行为。 此示例对五个矩形的 Width 属性进行动画处理，每个矩形使用了不同类型的重复行为。
<!-- RepeatBehaviorExample.xaml
This example shows how to use the RepeatBehavior property to make a timeline repeat. -->
<Page
xmlns="https://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="https://schemas.microsoft.com/winfx/2006/xaml"
WindowTitle="RepeatBehavior Example">
<Border HorizontalAlignment="Stretch">
<StackPanel Margin="20">
<!-- Create several rectangles to animate. -->
<Rectangle Name="ForeverRepeatingRectangle"
Fill="Orange" Width="50" Height="20" />
<Rectangle Name="FourSecondsRepeatingRectangle"
Fill="Orange" Width="50" Height="20" />
<Rectangle Name="TwiceRepeatingRectangle"
Fill="Orange" Width="50" Height="20" />
<Rectangle Name="HalfRepeatingRectangle"
Fill="Orange" Width="50" Height="20" />
<Rectangle Name="OneSecondRepeatingRectangle"
Fill="Orange" Width="50" Height="20" />
<!-- Create buttons to restart and stop the animations. -->
<StackPanel Orientation="Horizontal" Margin="0,20,0,0">
<Button Name="restartButton">Start Animations</Button>
<Button Name="stopButton" Background="#669900FF">Stop</Button>
<StackPanel.Triggers>
<EventTrigger SourceName="restartButton" RoutedEvent="Button.Click">
<BeginStoryboard Name="myBeginStoryboard">
<Storyboard>
<!-- Create an animation that repeats indefinitely. -->
<DoubleAnimation
Storyboard.TargetName="ForeverRepeatingRectangle"
Storyboard.TargetProperty="Width"
From="50" To="300" Duration="0:0:2" RepeatBehavior="Forever" />
<!-- Create an animation that repeats for four seconds. As a result, the
animation repeats twice. -->
<DoubleAnimation
Storyboard.TargetName="FourSecondsRepeatingRectangle"
Storyboard.TargetProperty="Width"
From="50" To="300" Duration="0:0:2" RepeatBehavior="0:0:4" />
<!-- Create an animation that repeats twice. -->
<DoubleAnimation
Storyboard.TargetName="TwiceRepeatingRectangle"
Storyboard.TargetProperty="Width"
From="50" To="300" Duration="0:0:2" RepeatBehavior="2x" />
<!-- Create an animation that repeats 0.5 times. The resulting animation
plays for one second, half of its Duration. It animates from 50 to 150. -->
<DoubleAnimation
Storyboard.TargetName="HalfRepeatingRectangle"
Storyboard.TargetProperty="Width"
From="50" To="300" Duration="0:0:2" RepeatBehavior="0.5x" />
<!-- Create an animation that repeats for one second. The resulting animation
plays for one second, half of its Duration. It animates from 50 to 150. -->
<DoubleAnimation
Storyboard.TargetName="OneSecondRepeatingRectangle"
Storyboard.TargetProperty="Width"
From="50" To="300" Duration="0:0:2" RepeatBehavior="0:0:1" />
</Storyboard>
</BeginStoryboard>
</EventTrigger>
<EventTrigger SourceName="stopButton" RoutedEvent="Button.Click">
<StopStoryboard BeginStoryboardName="myBeginStoryboard" />
</EventTrigger>
</StackPanel.Triggers>
</StackPanel>
</StackPanel>
</Border>
</Page>
有关完整示例，请参见 Animation Timing Behavior Sample（动画计时行为示例）。