Occurs before an application executes a request to cancel changes to the active record.
Syntax:
property BeforeCancel: TDataSetNotifyEvent;
Description:
Write a BeforeCancel event to take specific action before an application carries out a
request to cancel changes. BeforeCancel is called by the Cancel method before it cancels
a dataset operation such as Edit, Insert, or Delete.
An application might use the BeforeCancel event to record a user's changes in an undo
buffer.