ASP.NET MVC Viewmodel trouble...

Question

I've already started similar topic, but still didn't find final solution... So here I am with new one :) ... I'm developing NerdDinner from scratch and now I came to point where I define DinnerViewModel.
Following these instructions (starting from Listing 5) I came to this:

namespace Nerd.Controllers
{

    // View Model Classes  

    public class DinnerViewModel
    {
        public DinnerViewModel(List<Dinner> dinners)
        {
            this.Dinners = dinners;
        }

        public List<Dinner> Dinners { get; private set; }

    } 

    public class DinnerController : Controller
    {
        private DinnerRepository dinnerRepository = new DinnerRepository();

        ....

        public ActionResult NewDinners()
        {
            // Create list of products  
            var dinners = new List<Dinner>();
            dinners.Add(new Dinner(/*Something to add*/));

            // Return view  
            return View(new DinnerViewModel(dinners));
        }


    }
}

Also, the Dinner table in this new version of NerdDinner is a bit shortened (it contains of DinnerID, Title, EventDate and Description fields).

No matter what I try to add here dinners.Add(new Dinner(/*Something to add*/)); I always get following error

Error 1 'Nerd.Model.Dinner' does not contain a constructor that takes '1' arguments C:\Documents and Settings\ilija\My Documents\Visual Studio 2008\Projects\Nerd\Nerd\Controllers\DinnerController.cs 150 25 Nerd

Because I'm total beginner in C# and generally OOP, I have no idea what to do here... I suppose I need to declare a constructor, but how and where exactly?

Thanks,
Ile

Answer 1

The exception message says it all. Your Dinner object doesn't have a constructor that takes 1 argument. So you cannot do this :

new Dinner(someVariable)

Because there is no method in the Dinner class that lets you create a dinner object with one argument.

Answer 2

If you've been following the nerd dinner "tutorial" you've probably used Linq2Sql and the default generated code define Dineer with parameterless constructor (method called 'Dinner()').

Instead you can use properties to set the object's values:

Dinner dinner = new Dinner;
dinner.Title = "My dinner";
dinner.Description ="...";
// etc.

Answer 3

If you want to initialize values in new Dinner object, use this construction

dinners.Add(new Dinner() { Title = "DinnerTitle", Description = "DinnerDescription" });