ASP.NET MVC: How to transfer more than one object to View method?

Question

I finished NerdDinner tutorial and now I'm playing a bit with project. Index page shows all upcoming dinners:

    public ActionResult Index()
    {
        var dinners = dinnerRepository.FindUpComingDinners().ToList();
        return View(dinners);
    }

In DinnerRepository class I have method FindAllDinners and I would like to add to above Index method number of all dinners, something like this:

    public ActionResult Index()
    {
        var dinners = dinnerRepository.FindUpComingDinners().ToList();
        var numberOfAllDinners = dinnerRepository.FindAllDinners().Count();
        return View(dinners, numberOfAllDinners);
    }

Of course, this doesn't work. As I'm pretty new to OOP I would need help with this one.

Thanks,
Ile

Answer 1

Create view model:

public class DinnerViewModel
{
    public List<Dinner> Dinners { get; set; }
    public int NumberOfAllDinners { get; set; }
}

public ActionResult Index()
{
    var dinners = dinnerRepository.FindUpComingDinners().ToList();
    var numberOfAllDinners = dinnerRepository.FindAllDinners().Count();
    return View(new DinnerViewModel { Dinners = dinners, NumberOfAllDinners = numberOfAllDinners } );
}

Answer 2

You need to create a "wrapper" object that contains the objects you wish to pass as public properties of it. For instance, create an object called DinnerViewModel and give it two properties and set these with two properties, one a List called Dinners and one an int called DinnerCount. Then pass the DinnerViewModel to the view and you can then access Model.Dinners and Model.DinnerCount

Answer 3

Just simply use dinners.Count property instead.

Answer 4

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using System.Web.Mvc.Ajax;
using Nerd.Model;
using Nerd.Models;

namespace Nerd.Controllers
{

    // ViewModel Classes
    public class DinnerViewModel
    {
        List<Dinner> Dinners { get; set; }
        int DinnerCount { get; set; }
    }

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

        //
        // GET: /Dinner/

        public ActionResult Index()
    {
        var dinners = dinnerRepository.FindUpComingDinners().ToList();
        int dinnerCount = dinnerRepository.FindAllDinners().Count();

        return View(new DinnerViewModel {Dinners = dinners, DinnerCount = dinnerCount});
    }

       ...
    }
}

I tried this way but I get error that Dinners and DinnerCount are inaccessible. If I place public in front of them in DinnerViewModel this error disappears. Finally, I get this error:

The model item passed into the dictionary is of type 'Nerd.Controllers.DinnerViewModel' but this dictionary requires a model item of type 'System.Collections.Generic.IEnumerable`1[Nerd.Model.Dinner]'.

Index.aspx inherits this:

Inherits="System.Web.Mvc.ViewPage<IEnumerable<Nerd.Model.Dinner>>"

Where did I go wrong? Thanks for help!

Answer 5

In your case I would prefer the solution mentioned by LukLed.

In general you could of course also transfer multiple values from your controller to your view using ViewData:

ViewData["dinners"] = dinners;
ViewData["numberOfAllDinners"] = 150;
...

For more information also take a look at this link.

Answer 6

Guys, if you are talking about when you try to go to edit or create and you get this error, this should be the solution. I was encountering the same thing and this was a very easy fix. This is a little long, but it really is only a one line fix for each method. So, if the above dilemma was your issue, please continue to read and it might help you. Feel free to email me if you don't understand my wording

---

I figured it out. It seems as if everyone is trying to create or add elaborate methods to do fix an error that is extremely simple to fix. Remember, you start off using the ViewData inherts in you .aspx filesand returning the same in you return statements. Because of that, I figure that it was an issue with the Inherits attribute on the top of the ASP.NET files. But, if you are getting the error when trying to create or edit a new Dinner when you are on the 'Upcoming Dinners' page (generated from the Details.aspx and the LINQ file that gets all Dinners that are after todays date), go into your 'Controllers' directory, specifically the DinnerController.cs. Then look at the Edit and or Create methods. the answer lies right here. If you put breakpoints on these methods, you should be able to figure it out. If not, continue reading:

Look where it fails, the 'return...' line. Maybe I am the only person who forgot to change this, but my error is the same as people are getting in this page and this os how I fixed it.....the 'return(dinner)' line, in Create and Edit (and any others that you are having issues with), they are using the NerDinner.Model.Dinner / ViewData method. However, if you change it to the ViewModel return method instead, it should fix it, For example: 'return(new DinnerFormViewModel(dinner));', it should work for you. I hope this helps, as it was what my issue was. Just a simple overlook.

P.S. - I am not trying to insult anyone createing these extra methods. Maybe they are doing them for a reason. But if it is for an error that requires a logical fix, creating all of these new methods confuses the f@#$ out of me because I think that I should have done it that way and now I have to learn something new. So please, don't take any offense. It is just when you are trying to learn something new and you run into an error, and a hack is to write something new, it just turn my brain into marshmellow and I have to quit. But, of course your help is greatly appreciated:

-wrikgee

When angry, count ten; when very angry, a hundred - Thomas Jefferson