Question

I’m running into issues with multiple contexts and the main solution that comes up is to share the context between repositories however I haven’t found a good example on how to do this.

For reference, I’m using an MVC Web App to connect to my data layer. I’d like to have one context per user request (assuming this is correct).

Thanks,

Edit –

This is my solution with the help of BrokenGlass’s links and the following SO Question:

I essentially implemented the Unit Of Work pattern and Dependency Injection. I should have mentioned in addition to using MVC, I’m also using Ninject.

In a given repository constructor (see the link below for Unit Of Work pattern details):

public class PersonRepository : IPersonRepository
{
    private readonly MyContext _context;

    public PersonRepository(IUnitOfWork unitOfWork) 
    {
        if (unitOfWork == null)
            throw new ArgumentNullException("unitOfWork");

        _context = unitOfWork as MyContext;
    } 

    //...
}

In my MVC App in the NinjectMVC3 class (the key being the InRequestScope() method):

private static void RegisterServices(IKernel kernel)
{
     kernel.Bind<IUnitOfWork>().To<MyContext>().InRequestScope();
     kernel.Bind<IPersonRepository>().To<PersonRepository>();
     //...
}  

Answer 1

Your repository layer should provide a unit of work that represents a single request and uses a context object that is then used on all individual repositories that are needed to fulfill the request.

For HTTP / web apps specifically you can cache the db context in the HttpContext.Current.Items which stores shared data for each HTTP request. Also check out this similar SO thread for details: attaching linq to sql datacontext to httpcontext in business layer