Entity classes decoupled from LINQ to SQL provider for implementing the Repository pattern. How?

Question

I have looked over the Repository pattern and I recognized some ideas that I was using in the past which made me feel well.

However now I would like to write an applicat

Answer 1

The simplest way would be to decouple your entities from the datacontext: load the needed entity, decouple it from the DataContext, use it however you like, later use Attach() to couple it with a DataContext for saving.

Sadly LINQ has no method to decouple entities from a datacontext, but you can just clone them, that works nicely. Simplest way would be something like this:

public static T CloneEntity<T>(T source)
{
  DataContractSerializer dcs = new DataContractSerializer(typeof(T));
  using (Stream stream = new MemoryStream())
  {
    dcs.WriteObject(stream, source);
    stream.Seek(0, SeekOrigin.Begin);
    return (T)dcs.ReadObject(stream);
  }
}

Answer 2

I did something similar with WCF

1 On your DBML, set you Serialization mode to Unidirectional

2 Set ALL columns on your tables to UpdateCheck=false

3 Write your service something like the following:

   public class Service1 : IService1
    {
        public Company GetCompany(int companyId)
        {
            using (DataClasses1DataContext dc = new DataClasses1DataContext())
            {
                return (from c in dc.Companies where c.CompanyId == companyId select c).Single();
            }
        }


    public void SaveCompany(Company company)
    {
        using (DataClasses1DataContext dc = new DataClasses1DataContext())
        {
            dc.Companies.Attach(company, true);
            dc.SubmitChanges();
        }
    }

    public void InsertCompany(Company company)
    {
        using (DataClasses1DataContext dc = new DataClasses1DataContext())
        {
            dc.Companies.InsertOnSubmit(company);
            dc.SubmitChanges();
        }
    }
}

4 Add a service reference

Answer 3

I think you want POCO (Plain Old CLR Objects) support. LINQ to SQL has a adapter called Close2Poco.

But I would advise making the switch to Entity Framework, at the moment they also have a POCO adapter, but in v2 its expected to be supported out of the box.