public TransportMain(string type, string land, string stad)
        {
            InitializeComponent();
            using (TransportServiceClient tsc = new TransportServiceClient())
            {
                if (land.Equals(""))
                    land = null;

                if (stad.Equals(""))
                    stad = null;

                this.lastTransportResult = tsc.getTransport(type, land, stad);

                transportType[] tt = tsc.getAlleTransportTypes();

                if (this.lastTransportResult != null && this.lastTransportResult.Count() > 0)
                {
                    foreach (transport tr in this.lastTransportResult)
                    {
                        transportType ttp = new transportType();
                        foreach (transportType t in tt)
                        {
                            if (t.type_id == tr.type_id)
                            {
                                ttp = t;
                                break;
                            }
                        }

                        listBox1.Items.Add("[" + ttp.naam + "] " + tr.omschrijving);
                    }
                }
            }
        }