Assembly: System.Windows (in System.Windows.dll)
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 is capturing cursor movement..
The 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 in a derived class, make sure to call the base class’s method so that registered delegates receive the event.