Slider.OnMouseLeftButtonDown Method

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Provides class handling for the MouseLeftButtonDown event.

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


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


This implementation marks the MouseLeftButtonDown event as handled by setting the MouseButtonEventArgs.Handled property of the event data to true. In addition, it makes sure that the Slider control has the focus and has captured the mouse.

The OnMouseLeftButtonDown method allows derived classes to handle the event without attaching a delegate. This is the preferred technique for handling the event in a derived class.

Notes to Inheritors

When overriding OnMouseLeftButtonDown in a derived class, make sure to call the base class’s OnMouseLeftButtonDown method so that registered delegates receive the event.

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.