如何：检测鼠标按钮状态
更新：2007 年 11 月
此示例演示如何使用鼠标按钮事件和 MouseButtonState 属性来确定某个特定的鼠标按钮上是处于按下状态还是释放状态。
本示例包括一个可扩展应用程序标记语言 (XAML) 文件和一个代码隐藏文件。有关完整的示例，请参见检测鼠标按钮状态的示例示例。
示例
下面的代码创建了用户界面（它在 StackPanel 中包括了 TextBlock），并附加了 MouseLeftButtonDown 和 MouseLeftButtonUp 事件的事件处理程序。
<StackPanel Height="100" Width="100"
MouseLeftButtonDown="HandleButtonDown"
MouseLeftButtonUp="HandleButtonDown"
Background="#d08080"
DockPanel.Dock="Left"
>
<TextBlock>Click on Me</TextBlock>
</StackPanel>
下面的代码隐藏创建了 MouseLeftButtonUp 和 MouseLeftButtonDown 事件处理程序。 当按鼠标左键时，TextBlock 的维度将增加。 当释放鼠标左键时，TextBlock 的维度将恢复到原始的高度和宽度。
Partial Public Class Window1
Inherits Window
Public Sub New()
InitializeComponent()
End Sub
Private Sub HandleButtonDown(ByVal sender As Object, ByVal e As MouseButtonEventArgs)
' Casting the source to a StackPanel
Dim sourceStackPanel As StackPanel = CType(e.Source, StackPanel)
' If the button is pressed then make dimensions larger.
If e.ButtonState = MouseButtonState.Pressed Then
sourceStackPanel.Width = 200
sourceStackPanel.Height = 200
' If the button is released then make dimensions smaller.
ElseIf e.ButtonState = MouseButtonState.Released Then
sourceStackPanel.Width = 100
sourceStackPanel.Height = 100
End If
End Sub
End Class
public Window1()
{
InitializeComponent();
}
void HandleButtonDown(object sender, MouseButtonEventArgs e)
{
//Casting the source to a StackPanel
StackPanel sourceStackPanel = e.Source as StackPanel;
//If the button is pressed then make dimensions larger.
if (e.ButtonState == MouseButtonState.Pressed)
{
sourceStackPanel.Width = 200;
sourceStackPanel.Height = 200;
}
//If the button is released then make dimensions smaller.
else if (e.ButtonState == MouseButtonState.Released)
{
sourceStackPanel.Width = 100;
sourceStackPanel.Height = 100;
}
}
}