Assembly: PresentationFramework (in PresentationFramework.dll)
This method sets IsChecked to true when the user presses the plus key and to false when the user presses the minus key.Notes to Inheritors
If you override , always call the base implementation in your implementation. Failure to call the base implementation prevents base classes from handling the event with a class handler, which might change the run-time behavior of the final class. You can call the base implementation either before or after your special handling, depending on your requirements.