Generic Service Implementation - asp.net-mvc

Question

In my learning ASP.NET MVC 4 application, I use repository pattern and service layers. Entity framework and Autofac is used in the project. My data classes are simple and almost all operations are basic CRUD operations.
I have an abstract repository base as:
public abstract class RepositoryBase<T> where T : class
And this is a sample repository for the entity Sample1:
public class Sample1Repository : RepositoryBase<Sample1>, ISample1Repository
{
public Sample1Repository(IDatabaseFactory databaseFactory)
: base(databaseFactory)
{
}
}
public interface ISample1Repository : IRepository<Sample1>
{
}
This is my controller:
public class SampleController : Controller
{
private readonly ISampleService _sampleService;
public SampleController(ISampleService sampleService)
{
this._sampleService = sampleService;
}
}
And, lastly this is my service:
public interface ISampleService
{
IEnumerable<Sample1> GetSample1s();
Sample1 GetSample1(int id);
void CreateSample1(Sample1 item);
void DeleteSample1(int id);
void SaveSample1();
}
public class SampleService : ISampleService
{
private readonly ISample1Repository _sample1Repository;
private readonly IUnitOfWork _unitOfWork;
public SampleService(ISample1Repository sample1Repository, IUnitOfWork unitOfWork)
{
this._sample1Repository = sample1Repository;
this._unitOfWork = unitOfWork;
}
}
Now, I have these questions:
1) Do I need to create a separate class for each entity repository. (ie. another Sample2Repository for the entity Sample2)
2) Can I use a generic service for doing those CRUD tasks?
3) If generic service is possible. How can I register it/them in Autofac bootstrapper?

Answer 1

1) Do I need to create a separate class for each entity repository.
If you can, create a single generic IRepository<T> implementation and map that to this open generic interface.
2) Can I use a generic service for doing those CRUD tasks?
Of course you can, but the real question is: is it useful to do so? Seems to me that your ISampleService simply duplicates the logic from the IRepository<T>. It probably forwards to this repository. Seems like a useless abstraction to me. If your application is truly CRUD, you can inject your repository directly into your controller.
3) If generic service is possible. How can I register it/them in
Autofac bootstrapper?
You can map an open-generic interface to an open generic implementation as follows:
builder.RegisterGeneric(typeof(EntityFrameworkRepository<>))
.As(typeof(IRepository<>))
If you have many concrete (non-generic) IRepository<T> implementations and want to batch-register them, you can do this as follows:
builder.RegisterAssemblyTypes(typeof(IRepository<>).Assembly)
.AsClosedTypesOf(typeof(IRepository<>));