In the Component Inspector, select the object whose handler you want to rename
and select the Events tab on the property sheet.
Select the handler name you want to rename, and type the new name.
Alternatively, select the event in the property sheet and click the
ellipsis (...) button to display the Handlers dialog box.
If you displayed the Handlers dialog box, select the handler to rename in the
Handlers list, click Rename, and type the new name for the handler in
the Rename Handler dialog box that appears.