Question

I am trying to get information from a database, convert it to a list and return the CustomerList. This first bit of code works fine. The second example is where I’m trying to accomplish the same thing except the fields are coming from my database. What’s wrong with what I’m doing and how can I make this work? The second piece of code works elsewhere in my project but not here.

private SchoolIn.Models.CustomerList CreateCustomerList()
{
    return new SchoolIn.Models.CustomerList()
    {
        new SchoolIn.Models.Customer { Id = 1, Name      = "Patrick", Address = "Geuzenstraat 29", Place = "Amsterdam" },
        new SchoolIn.Models.Customer{ Id = 2, Name = "Fred", Address = "Flink 9a", Place = "Rotterdam" },
        new SchoolIn.Models.Customer { Id = 3, Name = "Sjonnie", Address = "Paternatenplaats 44", Place = "Enkhuizen" },
        new SchoolIn.Models.Customer { Id = 4, Name = "Henk", Address = "Wakerdijk 74", Place = "Utrecht" },
        new SchoolIn.Models.Customer { Id = 5, Name = "Klaas", Address = "Paternatenplaats 44", Place = "Plaantan" }
    };
}

private SchoolIn.Models.CustomerList CreateCustomerList()
{
    return new SchoolIn.Models.CustomerList()
    {
        SchoolInDB db = new SchoolIn.Models.SchoolInDB();
        var courseprogresses = db.CourseProgresses.Include(c => c.Course).Include(c => c.Teacher);
        return View(courseprogresses.ToList());
    };
}

Answer 1

First things first the second code is invalid C#. So I suppose it doesn’t event compile. You cannot use such expressions in an object initialization syntax. Please learn C# before getting into ASP.NET MVC.

The other problem is that your method is private and you are attempting to return View which is something that you do in a controller action. The view method returns an ActionResult whereas your method return type is SchoolIn.Models.CustomerList which once again is wrong.

So move this into some controller action where you would instantiate your database access context and then perform the query and return the model to the corresponding view for display:

public class HomeController: Controller
{
    ...

    public ActionResult CreateCustomerList()
    {
        SchoolInDB db = new SchoolIn.Models.SchoolInDB();
        var courseprogresses = db
            .CourseProgresses
            .Include(c => c.Course)
            .Include(c => c.Teacher)
            .ToList();
        return View(courseprogresses);
    }
}

and if you wanted to keep this into a separate method:

private List<SchoolIn.Models.CourseProgress> CreateCustomerList()
{
    SchoolInDB db = new SchoolIn.Models.SchoolInDB();
    return db
        .CourseProgresses
        .Include(c => c.Course)
        .Include(c => c.Teacher)
        .ToList();
}