procedure TEditForm.DeleteButtonClick(Sender: TObject);
var
    SubscriberNumber: integer;
begin
    if (SubscribersStringGrid.Row <> 0) then
    begin
        SubscriberNumber := NumberArray[SubscribersStringGrid.Row - 1];
        deleteSubscriber(SubscriberNumber);
        ShowButtonClick(Sender);
    end;
end;