/// <summary>
        /// Henter en liste fra disken
        /// </summary>
        private async void HentDataFraDiskAsync()
        {
            try
            {
                ObservableCollection <Booking> templist = await PersistencyService.HentDataFraDiskAsyncPS("Booking1.json");

                foreach (var booking in templist)
                {
                    OC_Bookings.Add(booking);
                }
            }
            catch (Exception)
            {
            }
        }
 /// <summary>
 /// fjerner valgte bookning fra listen
 /// </summary>
 private void RemoveBooking()
 {
     OC_Bookings.Remove(SelectedBooking);
 }