Notification that an object is about to be deleted from a rich edit control. The object is not necessarily being released when this member is called.
HRESULT DeleteObject(
  LPOLEOBJECT lpoleobj  
);
 No return value.
  Windows NT: Requires version 3.1 or later.
  Windows: Requires Windows 95 or later.
  Windows CE: Unsupported.
  Header: Declared in richole.h.
Rich Edit Controls Overview, Rich Edit OLE Interfaces, IRichEditOleCallback