Question

I have a simple method where I save the given customer information into the database using entity Framework:

    public Customer AddCustomer(Customer customer)
    {
        using (var context = DataObjectFactory.CreateContext())
        {
            context.AddObject("CustomerEntities", Mapper.Map(customer));

            context.SaveChanges();

            return customer;
        }
    }

Customer type is very simple, it consists of Id, and Name of the customer, so when we want to save a customer I simply pass a customer object to AddCustomer method, at this point the Id is null and the Name field contains the name I want save to the database.

This works fine, the name gets inserted into the database, however what I want to do is to get the saved customer Id back and return to the calling function, is there anyway of achieving this?

EDIT:

This is the Mapper method used:

internal static class Mapper
{
    internal static IList<Customer> Map(IEnumerable<CustomerEntity> entity)
    {
        return entity.Select(Map).ToList();
    }

    internal static Customer Map(CustomerEntity entity)
    {
        return new Customer
        {
            CustomerId = entity.CustomerId,
            Name = entity.Name
        };
    }

    internal static CustomerEntity Map(Customer customer)
    {
        return new CustomerEntity
        {
            CustomerId = customer.CustomerId,
            Name = customer.Name
        };
    }
}

Thanks

Answer 1

have a little doubt with the Mapping part, as we don’t know what Mapper.Map(customer) does return… But I’m quite sure that it does return a new instance of something… So customer.Id won’t be changed, as you don’t add customer to context, but Mapper.Map(customer)

EDIT : well, my guess was right (what a genius 😉 ). So that should be

public int AddCustomer(Customer customer)
{
    using (var context = DataObjectFactory.CreateContext())
    {
        var customerEntity = Mapper.Map(customer);
        context.AddObject("CustomerEntities", customerEntity);

        context.SaveChanges();

        return customerEntity.Id;
    }
}