Question

I have a complex object which has references to other objects, I am trying to save it from my web application.

so, in my webapplication, I call the business logic, and from the bl, I call the DAL Facade, and then the DAL.

When I execute the Insert method I am having the exception.

Code in the DAL layer, this is where the exception is raised.

public void InsertEcoBonusRequest(EcoBonusRequest ecoBonusRequest)
        {
            _context.EcoBonusRequests.Add(ecoBonusRequest);
        }

Code in the Unitofwork.cs

public void Save()
        {
            _context.SaveChanges();
        }

 private RequestBaseRepository _requestBaseRepository;

 public EcoBonusRequestRepository EcoBonusRequestRepository
            {
                get
                {
                    return _ecobonusworkflowRepository ??
                            (_ecobonusworkflowRepository = new EcoBonusRequestRepository(_context));
                }
            }

Code in the dal facade:

private  static readonly UnitOfWork UnitOfWork = new UnitOfWork();

        public void Save(EcoBonusRequest ecoBonusRequest)
        {
            UnitOfWork.EcoBonusRequestRepository.InsertEcoBonusRequest(ecoBonusRequest);
        }

Code in the BL

public void Save(EcoBonusRequest ecoBonusRequest)
        {
            EcoBonusRequestFacade.Save(ecoBonusRequest);

}


**Code in the page.aspx.cs, as you can see the element ecobonusworkflow is neverstored in the database, but the navigation entities are stored already.**

 var dealer = DealerBL.GetDealer(Nuteres);
  var requester = RequesterBL.GetRequester(int.Parse(DdlRequester.SelectedItem.Value));
                var selectedVehicle = VehicleBL.GetVehicle(VehicleInformationControl.Chassis);


var ecoBonusWorkflow = new EcoBonusRequest
                {
                    IsOnHold = true,
                    AmmountWithoutVAT = decimal.Parse(TxtVatExcluded.Text),
                    AmmountWithVAT = decimal.Parse(TxtVatIncluded.Text),
                    BrandReturnedVehicle = TxtBrandReturnedVehicle.Text,
                    ChassisReturnedVehicle = TxtChasisReturnedVehicle.Text,
                    Percentage = (decimal.Parse(TxtVatExcluded.Text)/VehicleInformationControl.InvoicedAmmount)*100,
                    Comments = TxtComments.Text,
                    Customer = new Customer
                    {
                        FirstName = TxtFirstName.Text,
                        LastName = TxtLastName.Text,
                        Address = new Address
                        {
                            Street = TxtStreet.Text,
                            Number = TxtNumber.Text,
                            Box = TxtBox.Text,
                            City = TxtCity.Text,
                            Zip = TxtZip.Text
                        }
                    },
                    CurrentStatus = "Approval1",
                    Dealer = dealer,
                    Requester = requester,
                    VehicleDesctructionDate = DateTime.Parse(TxtVehicleDestructionDateReturnedVehicle.Text, userCulture),
                    DestructionCertificateNumberReturnedVehicle = TxtDestructionCertificateNumberReturnedVehicle.Text,
                    TypeReturnedVehicle = TxtTypeReturnedVehicle.Text,
                    Vehicle = selectedVehicle
                };
                EcoBonusRequest = ecoBonusWorkflow;
                UploadFiles();
                RedirectToPage("~/Requests/confirmation.aspx");

Answer 1

The exception states that your entity, or navigation entities of the root entity is already attached to another context.
Depending on your architecture, you should either create a new context and attach it every time; or if you are reusing the context you should refresh the context with new values.

In your case, it seems you are creating a new context, but a previous context has not been disposed thus the entity is still attached to the older context. In this case, just reuse the older context instead of creating a new one.