Entity Framework Can Not Save My Change

Question

I'm using the following design:

I'm using AutoMapper for the domain/DTO conversions (both ways), Entity Framework Code First, and SQL Server 2012.

Each table has a field named RowVersion of type timestamp in order to check updates.

I'm using a DTO layer because my domain objects can't be serialized in WCF services, and I have a cycle in my domain layer.

Anyway, my problem is that when create a Bank (one table with a single page in the UI) I copy the values (BankCode, BankName) into BankDTO and in my service layer I convert BankDTO to BankDomain (the entity domain object for Bank) using AutoMapper, then call SaveChange.

That works, and I can update the bank too.

But when I edit one Bank and a bank branch, then convert BankDTO TO BankDomain and call SaveChange, that doesn't work. If I map BankDTO to BankDomain without AutoMapper, that works and the update is performed.

My BankDTO looks like this:

[Serializable]
public class BankModel
{

    public BankModel()
    {
        this.BankBranches = new List<BankBranchModel>();
    }
    public int? Id { get; set; }
    public byte[] RowVersion { get; set; } 
    public decimal BankCode { get; set; } 
    public string BankName { get; set; } 
    public string LatinCode { get; set; }

    public virtual ICollection<BankBranchModel> BankBranches { get; set; }

}

And the BankBranch DTO:

[Serializable]
public class BankBranchModel
{

    public BankBranchModel()
    {

    }

    public int BankId { get; set; }
    public decimal BranchCode { get; set; }
    public string BranchName { get; set; } 
    public int? ExecutiveUnitId { get; set; }
    public int? Id { get; set; } 
    public byte[] RowVersion { get; set; } 
    public BankModel Bank { get; set; } 

}

BankDomain:

public class Bank : BaseEntity
{
    public Bank()
    {
        this.BankBranches = new List<BankBranch>();     
    }
    public decimal BankCode { get; set; } 
    public string BankName { get; set; } 
    public string LatinCode { get; set; }

    public virtual ICollection<BankBranch> BankBranches { get; set; }
}

And BankBranchDomain:

public class BankBranch : BaseEntity
{
    public BankBranch()
    {
    }
    public int BankId { get; set; } 
    public decimal BranchCode { get; set; } 
    public string BranchName { get; set; } 

    public virtual Bank  Bank { get; set; }    
}

The SQL table is created like this:

CREATE TABLE [global].[Bank](
[Id] [int] NOT NULL,
[RowVersion] [timestamp] NOT NULL,
[BankCode] [numeric](18, 0) NOT NULL,
[BankName] [varchar](20) NOT NULL,
[LatinCode] [varchar](3) NOT NULL,
    CONSTRAINT [PKBnk] PRIMARY KEY CLUSTERED 
    (
        [Id] ASC
    ) WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF,      
            ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
 ) ON [PRIMARY]

CREATE TABLE [global].[BankBranch](
[Id] [int] NOT NULL,
[RowVersion] [timestamp] NOT NULL,
[BranchCode] [numeric](18, 0) NOT NULL,
[BranchName] [varchar](100) NOT NULL,
[BankId] [int] NOT NULL,
[ExecutiveUnitId] [int] NULL,
    CONSTRAINT [PK_BankBranch] PRIMARY KEY CLUSTERED 
    (
        [Id] ASC
    ) WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF,  
            ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]

And the update code:

using (var db = new AndishmandTestContext())
{
    Mapper.CreateMap<BankModel, Bank>();
    Mapper.CreateMap<Bank, BankModel>();

    Mapper.CreateMap<BankBranchModel, BankBranch>();
    Mapper.CreateMap<BankBranch, BankBranchModel>();

    var oldb = db.Banks.Include("BankBranches").Where(b => b.Id == 1);
    Bank bank = oldb.FirstOrDefault();
    BankModel bankmodel = new BankModel();
    Mapper.Map(bank, bankmodel);
}

After changing the BankModel in the UI layer, this code executes in the service layer:

var Newb = db.Banks.Include("BankBranches").Where(b => b.Id == 1);
Bank newbank = Newb.FirstOrDefault();
Mapper.Map(bankmodel, newbank);

Then the change is saved in the business layer:

db.SaveChanges();

If I map BankDto and BankBranchDto in BankDomain and BankBranchDomain instead of using Mapper.Map, then SaveChanges works - but I have to use AutoMapper.

Answer 1

You need to add object or values first which you have changed then save the changes.

  db.Banks.AddObject(---your object name or value which you want to add---);
   db.SaveChanges();

Answer 2

I finded my answer. I changeed my map and it woked

like this

            Mapper.CreateMap<BankModel, Bank>().ForMember(x => x.BankBranches, opt => opt.Ignore());
            //Mapper.CreateMap<BankModel, Bank>();
            Mapper.CreateMap<Bank, BankModel>();

            Mapper.CreateMap<BankBranchModel, BankBranch>().ForMember(x => x.Bank, opt => opt.Ignore());
            //Mapper.CreateMap<BankBranchModel, BankBranch>();
            Mapper.CreateMap<BankBranch, BankBranchModel>();

And then i most modify my domains like this

              //update bankdomain
            Mapper.Map(bankmodel, newbank);

            //Update bank branchdomain
            newbank.BankBranches.ToList().ForEach(bb => Mapper.Map(bankmodel.BankBranches.First(c => c.Id == bb.Id), bb));

            //Delete branchdomain
            foreach (var bBmodel in bankmodel.BankBranches.Where(bB => bB.IsDeleted == true))
            {
                newbank.BankBranches.Remove(newbank.BankBranches.Where(bb => bb.Id == bBmodel.Id).First());
            }

            //Add branchdomain
            foreach (var bBM in bankmodel.BankBranches.Where(c => c.Id == null))
            {
                newbank.BankBranches.Add(Mapper.Map<BankBranch>(bBM));
            }

and then

db.SaveChanges();