On Enter(EventArgs) Method
Raises the Enter event.
protected: override void OnEnter(EventArgs ^ e);
protected override void OnEnter (EventArgs e);
override this.OnEnter : EventArgs -> unit
Protected Overrides Sub OnEnter (e As EventArgs)
Raising an event invokes the event handler through a delegate. For more information, see Handling and Raising Events.
The OnEnter method also allows derived classes to handle the event without attaching a delegate. This is the preferred technique for handling the event in a derived class.