Ends a change or batch of changes. Calls to this method are counted; you must call this method once for every call to BeginChange . Note: If BeginChange was called with ChangeContexts.UI, ChangeContexts.Program, ChangeContexts.Drop or ChangeContexts.UI.Tree and Changed() was called between the calls to BeginChange and EndChange(), the last call to EndChange() will raise the ContentChanged event.