Solved

The model item passed into the dictionary is of type 'System.Collections.Generic.List' but this dictionary requires a model item of type 'System.Collections.Generic.IEnumberable'

Posted on 2014-03-18
3
4,309 Views
Last Modified: 2014-03-23
I have an MVC 4 application that has a model developed using EF 5.0 (Code First).  I am investigating TDD and had to make changes to the code generated by the model in order to get my unit tests to work.  Now that my unit tests work I am getting the following error when I try and run the application.

System.InvalidOperationException: The model item passed into the dictionary is of type 'System.Collections.Generic.List`1[AppCatalog.Models.AppCatalog_Database]', but this dictionary requires a model item of type 'System.Collections.Generic.IEnumerable`1[AppCatalogData.AppCatalog_Database]'.

Open in new window


Here is my controller:
namespace AppCatalog.Controllers
{
    public class DBCatalogController : Controller
    {
        private IAppCatalog db { get; set; }

        public DBCatalogController(IAppCatalog dataContext = null)
        {
            db = dataContext ?? new AppCatalogContainer();
        }
        public DBCatalogController()
        {
            db = new AppCatalogContainer();
        }

        //
        // GET: /DBCatalog/

        public ViewResult Index()
        {
            ViewBag.Title = "Application Catalog -> Database Catalog";

            var appcatalog_database = db.AppCatalog_Database.Include(a => a.AppCatalog_ServerType);
            return View(appcatalog_database.ToList());
        }
   }
}

Open in new window


Here is the model definition in my view:
@model IEnumerable<AppCatalogData.AppCatalog_Database>

Open in new window


Here is my Interface definition:
namespace AppCatalog.Models 
{
    public interface IAppCatalog 
    {
        IDbSet<AppCatalog_Database> AppCatalog_Database { get; set; }
        IDbSet<AppCatalog_ServerType> AppCatalog_ServerType { get; set; }
        IDbSet<AppCatalog_DBConnection> AppCatalog_DBConnection { get; set; }
        IDbSet<AppCatalog_Environment> AppCatalog_Environment { get; set; }
        IDbSet<AppCatalog_PIIData> AppCatalog_PIIData { get; set; }
        IDbSet<AppCatalog_Application> AppCatalog_Application { get; set; }
        IDbSet<AppCatalog_ApplicationTable> AppCatalog_ApplicationTable { get; set; }

        int SaveChanges();
        void Dispose();
    }

Open in new window


Here is the AppCatalogContainer definition:
namespace AppCatalog.Models
{
    using System;
    using System.Data.Entity;
    using System.Data.Entity.Infrastructure;
    
    public partial class AppCatalogContainer : DbContext, IAppCatalog
    {
        public AppCatalogContainer()
            : base("name=AppCatalogContainer")
        {
        }
    
        protected override void OnModelCreating(DbModelBuilder modelBuilder)
        {
            throw new UnintentionalCodeFirstException();
        }
    
        public IDbSet<AppCatalog_Database> AppCatalog_Database { get; set; }
        public IDbSet<AppCatalog_ServerType> AppCatalog_ServerType { get; set; }
        public IDbSet<AppCatalog_DBConnection> AppCatalog_DBConnection { get; set; }
        public IDbSet<AppCatalog_Environment> AppCatalog_Environment { get; set; }
        public IDbSet<AppCatalog_PIIData> AppCatalog_PIIData { get; set; }
        public IDbSet<AppCatalog_Application> AppCatalog_Application { get; set; }
        public IDbSet<AppCatalog_ApplicationTable> AppCatalog_ApplicationTable { get; set; }
    }
}

Open in new window


I'm not sure what change I need to make to the View or the Controller to get this to work.  Everything worked fine until I made the changes for the unit testing.

Any help is greatly appreciated!
0
Comment
Question by:dyarosh
  • 2
3 Comments
 
LVL 20

Expert Comment

by:Daniel Van Der Werken
ID: 39937343
Well, it looks like you are returning a List() and it is expecting an IEnumerable<> back.

So, I think these lines of code are the issue:

var appcatalog_database = db.AppCatalog_Database.Include(a => a.AppCatalog_ServerType);
return View(appcatalog_database.ToList());

Open in new window


Instead of doing the .ToList(), do as documented here:
http://msdn.microsoft.com/en-us/library/bb739071(v=vs.110).aspx

I would do:

return View(appcatalog_database.IEnumerable<AppCatalogData.AppCatalog_Database>().GetEnumerator();

Open in new window


...or something like that. I don't have your code, so I can't fiddle with it.
0
 

Accepted Solution

by:
dyarosh earned 0 total points
ID: 39937486
I found the problem.  I had to make sure my model derived from DbContext and my interface (IAppCatalog).
0
 

Author Closing Comment

by:dyarosh
ID: 39948428
I found the problem on my own.
0

Featured Post

Simplifying Server Workload Migrations

This use case outlines the migration challenges that organizations face and how the Acronis AnyData Engine supports physical-to-physical (P2P), physical-to-virtual (P2V), virtual to physical (V2P), and cross-virtual (V2V) migration scenarios to address these challenges.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Just a quick little trick I learned recently.  Now that I'm using jQuery with abandon in my asp.net applications, I have grown tired of the following syntax:      (CODE) I suppose it just offends my sense of decency to put inline VBScript on a…
It was really hard time for me to get the understanding of Delegates in C#. I went through many websites and articles but I found them very clumsy. After going through those sites, I noted down the points in a easy way so here I am sharing that unde…
This tutorial gives a high-level tour of the interface of Marketo (a marketing automation tool to help businesses track and engage prospective customers and drive them to purchase). You will see the main areas including Marketing Activities, Design …
Along with being a a promotional video for my three-day Annielytics Dashboard Seminor, this Micro Tutorial is an intro to Google Analytics API data.

770 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question