ButtonBase.OnMouseLeftButtonUp Method

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Provides class handling for the MouseLeftButtonUp event that occurs when the left mouse button is released while the mouse pointer is over this control.

Namespace:  System.Windows.Controls.Primitives
Assembly:  System.Windows (in System.Windows.dll)


Protected Overrides Sub OnMouseLeftButtonUp ( _
    e As MouseButtonEventArgs _
protected override void OnMouseLeftButtonUp(
    MouseButtonEventArgs e



Exception Condition

e is nulla null reference (Nothing in Visual Basic).


This method marks the MouseLeftButtonUp event as handled by setting the MouseButtonEventArgs.Handled property of the event data to true when the button is enabled and its ClickMode is not set to Hover. Since this method marks the MouseLeftButtonUp event as handled in some situations, you should use the Click event instead to detect a button click.

Notes to Inheritors

If you override OnMouseLeftButtonUp, always call the base implementation in your OnMouseLeftButtonUp implementation. Failure to call the base implementation prevents base classes from handling the event with a class handler, which might change the run-time behavior of the final class. You can call the base implementation either before or after your special handling, depending on your requirements.

Version Information


Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0


For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.