Occurs when the value of the CurrentState property changes.
Assembly: System.Windows (in System.Windows.dll)
XMLNS for XAML: Not mapped to an xmlns.
It is possible for the event to be raised multiple times before its event handlers are executed.
Although this event occurs when the CurrentState becomes invalid, that does not necessarily mean that the CurrentState property has a new value. For example, the CurrentState property might have switched from Playing to Buffering and back to Playing so rapidly that only a single event was raised, in which case the property will not appear to have changed values. Also, your application should not assume an order in which the events occur, particularly for the transient states such as "Buffering". One of the transient states may have been skipped over in event reporting because it happened so rapidly.