Edit line, edit box, combo box, edit table.
If an action that can be undone has been performed against the control, CANUNDO returns true.
status = Get_Property(objectname, "CANUNDO")
To undo an action, use the Send_Message function with the UNDO message. The CANUNDO property is used only with Get_Property.
Boolean value. True if the last operation against the control can be undone.