Question

I can use default design of MVC solution. For example, controller:

public class ProductController : Controller
   {
       private Entities db = new Entities();

       public ViewResult Details( int id )
          {
              Product product = db.Products.Single( p => p.ID == id );
              return View( product );
          }
    }

But I saw in some large projects, to call any method, they used only service, for example

public class ProductController : Controller<ISomeService>
{
 public ViewResult Details( int id )
    {
       Product product = MyService.GetProductById();
       return View( product );
    }
}

and not using database instance in the controller such as:

private Entities db = new Entities();

Models, DB and Business Logic are different projects in solution.

From where can I learn about this structure in any sample?
(sorry for bad English)

Answer 1

I would take a look at using dependency injection with ASP.NET MVC, here’s an article on the subject:

http://weblogs.asp.net/shijuvarghese/archive/2010/04/30/dependency-injection-in-nerddinner-app-using-ninject.aspx

Then take a look at using a Repository/UnitOfWork pattern with Entity Framework, another article:

http://www.codeproject.com/Tips/309753/Repository-Pattern-with-Entity-Framework-4-1-and-C

And if you’re not interested in doing all this code on your own, you can use, or at least take a look at how it can be done, here:

http://mvcbootstrap.codeplex.com