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Linq to SQL Row Not Found or Changed Exception on Insert Operation Ajax Postback in MVC3
at System.Data.Linq.ChangeProcessor.SubmitChanges(ConflictMode failureMode)
   at System.Data.Linq.DataContext.SubmitChanges(ConflictMode failureMode)
   at System.Data.Linq.DataContext.SubmitChanges()
   at ManageMAT.Controllers.FieldTripController.RouteAdd(Int32 id, FormCollection collection)

[HttpPost]
        public ActionResult RouteAdd(int id, FormCollection collection)
        {
            FieldTrip trip = context.FieldTrips.Single(ft => ft.ID == id);

            if (trip == null) return Json(new { success = false, message = "Field trip not found." }); ;

            try
            {

                FieldTripRoute tripRoute = new FieldTripRoute();

                tripRoute.FieldTripID = trip.ID;
                tripRoute.Date = DateTime.Parse(collection["Date"]);
                tripRoute.ArrivalTime = DateTime.Parse(collection["ArrivalTime"] + " " + DateTime.Now.ToShortDateString());
                tripRoute.DepartureTime = DateTime.Parse(collection["DepartureTime"] + " " + DateTime.Now.ToShortDateString());
                tripRoute.Destination = collection["Destination"];
                tripRoute.PickupLocation = collection["PickupLocation"];
                tripRoute.RouteID = Convert.ToInt32(collection["RouteID"]);

                context.FieldTripRoutes.InsertOnSubmit(tripRoute);
                context.SubmitChanges();

                return Json(new { success = true, message = "Success!" });
            }
            catch (Exception ex)
            {
                return Json(new { success = false, message = ex.Message });
            }
        }