protected void OnRowDeleting(object sender, GridViewDeleteEventArgs e)
        {
            int            index     = e.RowIndex;
            string         departure = GridView.Rows[index].Cells[1].Text;
            string         arrival   = GridView.Rows[index].Cells[2].Text;
            FlightsService service   = Service.getInstanse().flightService;

            service.DeleteFlightPrice(departure, arrival);
            UpdateAllTable();
        }