#602 – Accessing Information in RoutedEventArgs

All predefined routed events in WPF are declared as instances of a delegate type that passes back either an instance of RoutedEventArgs or of some subclass of RoutedEventArgs.

public delegate void RoutedEventHandler(object sender, RoutedEventArgs e);

The RoutedEventArgs type includes the following properties, which you can make use of in your event handlers:

  • Handled – has event been handled yet?
  • OriginalSource – original low-level element where the event originated (e.g. sub-element in a control)
  • RoutedEvent – an instance of the associated routed event
  • Source – element where the event originated

Note that if the event is bubbling or tunneling, the Source property will refer to the element where the event originated, while the sender parameter will refer to the element that raised the event.  If the event is bubbling or tunneling, this element may be higher up the logical tree than the source element.

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