private void button1_Click(object sender, RoutedEventArgs e)
        {
            Match mat = Regex.Match(tb_personen.Text, "[0-9]*");

            if (mat.Success)
            {
                using (FlightServiceClient fsc = new FlightServiceClient())
                {
                    Person p = new Person();

                    p.name = CommonMethods.loginUser.name;
                    p.lastName = CommonMethods.loginUser.lastname;
                    p.phone = CommonMethods.loginUser.telefoon;
                    p.email = CommonMethods.loginUser.email;

                    string bookid = fsc.bookFlight(selectedFlight.flightID, p,  Int32.Parse(tb_personen.Text), (string)cb_klasse.SelectedValue);

                    if (bookid.Equals(""))
                    {
                        tb_err.Foreground = Brushes.Red;
                        tb_err.Text = "Er is een error voorgekomen tijdens het boeken.";
                    }
                    else
                    {
                        OracleConnection oc = CommonMethods.GetConnection();
                        oc.Open();

                        OracleCommand ocmd = oc.CreateCommand();
                        ocmd.CommandText = String.Format("INSERT INTO BOOKING (IDENTIFIER, IDENTIFIER2,  TYPE, END_PERSOON) VALUES ('{0}', '{1}', '{2}', '{3}')",
                            bookid,
                            selectedFlight.flightID,
                            "flight",
                            CommonMethods.loginUser.id);
                        ocmd.ExecuteNonQuery();
                        oc.Close();

                        CommonMethods.GetFrame(this).Navigate(new ResultPage());
                    }
                }
            }
        }