DocumentManager.Invalidate Method

Name	Parameters	Description
Invalidate()	none	Invalidates the region occupied by the DocumentManager (adds it to the update region that will be repainted during the next paint operation), and causes a paint message to be sent to the DocumentManager.
Invalidate(Rectangle)	rect	Invalidates the specified region occupied by the DocumentManager (adds it to the update region that will be repainted during the next paint operation), and causes a paint message to be sent to the DocumentManager.