How to: Detect Mouse Button State
This example shows how to use mouse button events and the MouseButtonState property to determine whether a specific mouse button is pressed or released.
This example consists of a Extensible Application Markup Language (XAML) file and a code behind file.
Example
The following code creates the user interface, which consists of a TextBlock inside a StackPanel, and attaches event handlers for the MouseLeftButtonDown and MouseLeftButtonUp events.
<StackPanel Height="100" Width="100"
MouseLeftButtonDown="HandleButtonDown"
MouseLeftButtonUp="HandleButtonDown"
Background="#d08080"
DockPanel.Dock="Left"
>
<TextBlock>Click on Me</TextBlock>
</StackPanel>
The following code behind creates the MouseLeftButtonUp and MouseLeftButtonDown event handlers. When the left mouse button is pressed, the dimensions of the TextBlock are increased. When the left button is released, the dimensions of the TextBlock are restored to the original height and width.
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;
}
}
}