Removes a handler for the SourceChanged event from the provided element.
Assembly: PresentationCore (in PresentationCore.dll)
Even though this is a routed event, there are special restrictions placed on this event that differ from normal routed event behavior, due to the relatively small number of elements in a typical application scenario that would concern themselves with handling this event.
The C# += and -= event handler syntaxes, and other language specific handler syntaxes, are not supported, because the event itself is not exposed as public. Only the PresentationSource utility methods for adding and removing the handlers directly are supported.