procedure TForm1.OPCServerDatachange(Sender: TObject; ItemList: TdOPCItemList); var i: integer; Item: TdOPCItem; begin for i := 0 to ItemList.Count - 1 do // more than one item possible begin Item := ItemList[i]; Memo1.Lines.Add(format('Item %s Value %s', [Item.ItemId, Item.ValueStr])); end; end;