Integer via TempData @ C# ASP.NET MVC3 EntityFramework

Question

I have this problem with probing integer from TempData as it sees DempData["sth"] as object, not as integer itself. Here is my Create method I'm sending my integer into the TempData:

public ActionResult Create(int CustomerId, int qSetId, int Count)
{
    qSet qset = db.qSets.Find(qSetId);
    TempData["qSetId"] = qset.Id;
    Customer customer = db.Customers.Find(CustomerId);
    TempData["CustomerId"] = customer.Id;
    List<Relation> relations = db.Relations.Where(r => r.qSetId.Equals(qSetId)).ToList<Relation>();
    Question question = new Question();
    List<Question> questions = new List<Question>();
    foreach (Relation relation in relations)
    {
        question = db.Questions.Find(relation.QuestionId);
        if (questions.Contains<Question>(question).Equals(false))
            questions.Add(question);
    }
    if (questions.Count<Question>().Equals(Count).Equals(false))
    {
        TempData["QuestionId"] = questions[Count].Id;
        TempData["QuestionType"] = questions[Count].Type;
        ViewBag["QuestionContent"] = questions[Count].Content;
        TempData["Count"] = Count + 1;
        return View();
    }
    else
    {
        return RedirectToAction("ThankYou");
    }
}

And here is the other method, probing this data:

[HttpPost]
public ActionResult Create(Answer answer)
{                               
    answer.QuestionId = TempData["QuestionId"];
    answer.CustomerId = TempData["CustomerId"];

    if (ModelState.IsValid)
    {
        db.Answers.Add(answer);
        db.SaveChanges();
        return RedirectToAction("Create", new { CustomerId = TempData["CustomerId"], qSetId = TempData["qSetId"], Count = TempData["Count"] });
    }

    ViewBag.CustomerId = new SelectList(db.Customers, "Id", "eAdress", answer.CustomerId);
    ViewBag.QuestionId = new SelectList(db.Questions, "Id", "Name", answer.QuestionId);
    return View(answer);
}

Errors are present at:

answer.QuestionId = TempData["QuestionId"];
answer.CustomerId = TempData["CustomerId"];

And go like this:

Cannot implicitly convert type 'object' to 'int'. An explicit conversion exists (are you missing a cast?)

Any help?

Answer 1

The solution to this is called "unboxing". It's a straight cast from object to int:

answer.QuestionId = (int)TempData["QuestionId"];

Answer 2

I had the same issue in my code.

Both of these solutions worked:

    answer.QuestionId = Convert.ToInt32(TempData["QuestionId"];

and

    answer.QuestionId = (int)TempData["QuestionId"];

However, the (int) cast will not work in every instance, because not every object can be implicitly cast to int. For this reason, it's safer to use Convert.ToInt32()

Answer 3

int id = Convert.ToInt32(TempData["QuestionId"].ToString());