private DataGridViewComboBoxColumn GetGatewayComboBox(int conn_id)
        {
            DataGridViewComboBoxColumn cmb = new DataGridViewComboBoxColumn()
            {
                //CellTemplate = cell,
                Name             = "IPGateway",
                HeaderText       = "Шлюзы",
                DataPropertyName = "IPGateway", // Tell the column which property it should use
                DisplayMember    = "IPGateway",
                ValueMember      = "IPGateway",
                //Width = 120,
                AutoSizeMode = DataGridViewAutoSize‌​ColumnMode.Fill,
            };
            WMIMethods     methods = new WMIMethods();
            List <Gateway> gtwlist = methods.GetGatewayArray(conn_id);

            if (gtwlist.Count > 0)
            {
                var bindsList = new BindingList <Gateway>(gtwlist);
                var source    = new BindingSource(bindsList, null);
                cmb.DataSource = source;
            }

            return(cmb);
        }
        protected override void OnFormClosing(FormClosingEventArgs e)
        {
            base.OnFormClosing(e);

            DbMethods         DB              = new DbMethods();
            WMIMethods        methods         = new WMIMethods();
            List <Connection> Connection_list = methods.GetNetworkDevices();
            List <DNS>        DNS_list        = methods.GetDNSArray(Connection_list[0].Id);
            List <Gateway>    Gateway_list    = methods.GetGatewayArray(Connection_list[0].Id);

            if (Connection_list.Count > 0)
            {
                DB.SaveConnectionTable(Connection_list, DNS_list, Gateway_list);
            }

            //DB.ReadConnectionHistory(ref Connection_list);

            if (e.CloseReason == CloseReason.WindowsShutDown)
            {
                return;
            }
        }