MVC - Multiple models in a view - asp.net-mvc

Question

I'm using MVC (for the first time) with Entity framework, Database first
What I want to do is display data from a database in a single view. I created the database first, then I made a ADO.NET Entity Data Model based from the database that contains all the tables. I then created a Index view that was strongly typed with my Entity Data Model as model.
In my Index I have at the top
#model IEnumerable<Forum6.Models.Forum>
This allows me to get the rows from the table "Forum" from my database. If I try to add an extra model I get I get this error message when I run:
Line 1: #model IEnumerable<Forum6.Models.Forum>
Line 2: #model2 IEnumerable<Forum6.Models.Post>
Parser Error Message: Only one 'model' statement is allowed in a file.
After searching for an answer I found this: Two models in one view in ASP MVC 3
The answer was to create a ViewModel (ParentModel) that contained all the Models (Tables).
This is the ViewModel I created:
public class ViewModel
{
public IEnumerable<Forum6.Models.Forum> Forum { get; set; }
public IEnumerable<Forum6.Models.Post> Post { get; set; }
public IEnumerable<Forum6.Models.Topics> Topics { get; set; }
public IEnumerable<Forum6.Models.Users> Users { get; set; }
public IEnumerable<Forum6.Models.PrivMsg> PrivMsg { get; set; }
public IEnumerable<Forum6.Models.Permission> Permission { get; set; }
}
I edited my controller to look like this:
public class HomeController : Controller
{
// ForumDBEntities old_db = new ForumDBEntities();
ViewModel db = new ViewModel();
public ActionResult Index()
{
return View(db);
}
}
Then replaced the old Index view with a new strongly typed view that used the ViewModel as model. Which contains:
#model IEnumerable<Forum6.Models.ViewModel>
Trying to run this gives me this error:
The model item passed into the dictionary is of type 'Forum6.Models.ViewModel', but this dictionary requires a model item
of type
'System.Collections.Generic.IEnumerable`1[Forum6.Models.ViewModel]
How do I make the "ViewModel" enumarable? Or is my error elsewhere?

Answer 1

You'll need to change #model IEnumerable<Forum6.Models.ViewModel> to #model Forum6.Models.ViewModel as you're wrapping your IEnumerables inside a single ViewModel.
A good rule of thumb is to have a 1:1 relationship between your ViewModel and View.
This might be a good read for you: http://lostechies.com/jimmybogard/2009/06/30/how-we-do-mvc-view-models/ (just ignore the automapper part if you don't want to go that route)
You'll also need to put in actual data in your ViewModel since
ViewModel db = new ViewModel();
public ActionResult Index()
{
return View(db);
}
will just give your view an empty ViewModel.
One way to do it would be.
public ActionResult Index()
{
var model = new ViewModel
{
Forum = db.GetForum(),
Post = db.GetPost(),
Topic = you get the idea
};
return View(model);
}
One last thing when naming properties or variables in general you should use the plural verb when it contains a list. So your ViewModel would be.
public class ViewModel
{
public IEnumerable<Forum6.Models.Forum> Forums { get; set; }
public IEnumerable<Forum6.Models.Post> Posts { get; set; }
public IEnumerable<Forum6.Models.Topics> Topics { get; set; }
public IEnumerable<Forum6.Models.Users> Users { get; set; }
public IEnumerable<Forum6.Models.PrivMsg> PrivMsgs { get; set; }
public IEnumerable<Forum6.Models.Permission> Permissions { get; set; }
}

Answer 2

Change #model IEnumerable<Forum6.Models.ViewModel> to #model Forum6.Models.ViewModel as you are passing a single instance of a ViewModel class and not a collection of them.
All your collections are passed in a single instance of a view model.