您不能同时为两个属性设置动画下面的代码可以帮助您为名为 myWindow 的窗口的高度和宽度设置动画
<Button Content="Click">
<Button.Triggers>
<EventTrigger RoutedEvent="Button.Click">
<EventTrigger.Actions>
<BeginStoryboard >
<Storyboard RepeatBehavior="Forever" AutoReverse="False">
<DoubleAnimation Storyboard.TargetName="myWindow"
Storyboard.TargetProperty = "(Window.Height)"
To="300" Duration="0:0:5"/>
<Storyboard RepeatBehavior="Forever" AutoReverse="False">
<DoubleAnimation Storyboard.TargetName="myWindow"
Storyboard.TargetProperty = "(Window.Width)"
To="300" Duration="0:0:5"/>
</Storyboard>
</Storyboard>
</BeginStoryboard>
</EventTrigger.Actions>
</EventTrigger>
</Button.Triggers>
</Button>