NOTE: this article relates to our Windows Forms annotations components, not our web controls.
After the user has finished creating an annotation, the AnnotationController's AnnotationCreated event will fire. All you have to do is add an event handler for the AnnotationCreated event to receive this notification.
NOTE: If you are using the AnnotateViewer, this event is located in the AnnotateViewer.Annotations object.
Original Article:
Q10074 - INFO: How do I know when an annotation is finished being used by a user?