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The ObjectContext instance has been disposed and can no longer be used for operations that require a connection in mvc5 view

I'm trying to do a loop in mvc5 view for particular model properties but I'm getting an error:
Additional information: The ObjectContext instance has been disposed
and can no longer be used for operations that require a connection.
This is the view I have:
#using App.Models
#model App.Portal.WebUI.Models.ManageViewModel
#{
ViewBag.Title = "Edit";
}
<h2>Edit</h2>
<div class="container">
<div class="col-md-9">
<div class="col-md-12">
<div class="form-group">
#Html.LabelFor(m => m.AUser.Id)
<label>#Html.DisplayFor(m => m.AUser.Id)</label>
</div>
<div class="form-group">
#Html.LabelFor(m => m.AUser.FirstName)
#Html.TextBoxFor(m => m.AUser.FirstName)
</div>
<div class="form-group">
#Html.LabelFor(m => m.AUser.PhoneNumber)
#Html.TextBoxFor(m => m.AUser.PhoneNumber)
</div>
<div class="form-group">
</div>
</div>
<div class="col-md-12">
<div class="form-group"> </div>
<div class="form-group">
#Html.LabelFor(m => m.AUser.LastName)
#Html.TextBoxFor(m => m.AUser.LastName)
</div>
<div class="form-group">
#Html.LabelFor(m => m.AUser.Email)
#Html.TextBoxFor(m => m.AUser.Email)
</div>
</div>
</div>
<div class="col-md-3">
#foreach (AspNetRole userRole in Model.AUser.AspNetRoles)
{
#Html.CheckBox(userRole.Name, true)
#Html.Label(userRole.Name)<br />
}
</div>
</div>
The error happens in the foreach loop.
Any idea what am I doing wrong?
Update
Code added:
ManageViewModel model = new ManageViewModel();
if (id.HasValue)
{
using (var db = new DbContext())
{
AspNetUser user = (from p in db.AspNetUsers
where p.Id == id
select p).First();
model.AUser = user;
List<AspNetRole> roles = (from r in db.AspNetRoles
select r).ToList();
model.RoleList = roles;
}
}

My guess without seeing how you populate the Model class, is that the query for AspNetRoles has not actually been executed yet, and is doing so when you start iterating over the list with the foreach. The db context has been disposed in the controller, and so can no longer fetch the list results at that point.
When you populate the Model data in the controller, try doing .ToList() at the end of the query where you populate AspNetRoles, which will execute the query immediately. Hope this helps!

#foreach (AspNetRole userRole in Model.RoleList)
{
#Html.CheckBox(userRole.Name, true)
#Html.Label(userRole.Name)<br />
}
Don't use Entities connected to the DB in your ViewModel! NEVER!! It causes issues like you have just encountered. Separate layers. Read about separation of concerns separation of concerns

MVC 4 Optimistic concurrency exception

Having faced this issue (I wanted to allow an edit by using a bootstrap modal window, i'm using MVC4 and entity framework), when I want to save my changes, I have this error message since I'm using the modal window :
Store update, insert, or delete statement affected an unexpected number of rows (0). Entities may have been modified or deleted since entities were loaded. Refresh ObjectStateManager entries.
Here are my actions :
[HttpGet]
public ActionResult EditPerson(long id)
{
var person = db.Persons.Single(p => p.Id_Person == id);
ViewBag.Id_ProductPackageCategory = new SelectList(db.ProductPackageCategories, "Id_ProductPackageCategory", "Name", person.Id_ProductPackageCategory);
return PartialView("_EditPerson", person);
}
[HttpPost]
public ActionResult EditPerson(Person person)
{
ViewBag.Id_ProductPackageCategory = new SelectList(db.ProductPackageCategories, "Id_ProductPackageCategory", "Name", person.Id_ProductPackageCategory);
if (ModelState.IsValid)
{
ModelStateDictionary errorDictionary = Validator.isValid(person);
if (errorDictionary.Count > 0)
{
ModelState.Merge(errorDictionary);
return View(person);
}
db.Persons.Attach(person);
db.ObjectStateManager.ChangeObjectState(person, EntityState.Modified);
db.SaveChanges();
return View("Index");
}
return View(person);
}
My partial view :
#model BuSIMaterial.Models.Person
<div class="modal-header">
<button type="button" class="close" data-dismiss="modal" aria-hidden="true">×</button>
<h3 id="myModalLabel">Edit</h3>
</div>
<div>
#using (Ajax.BeginForm("EditPerson", "Person", FormMethod.Post,
new AjaxOptions
{
InsertionMode = InsertionMode.Replace,
HttpMethod = "POST",
UpdateTargetId = "table"
}))
{
#Html.ValidationSummary()
#Html.AntiForgeryToken()
<div class="modal-body">
<div class="editor-label">
First name :
</div>
<div class="editor-field">
#Html.TextBoxFor(model => model.FirstName, new { maxlength = 50 })
#Html.ValidationMessageFor(model => model.FirstName)
</div>
<div class="editor-label">
Last name :
</div>
<div class="editor-field">
#Html.TextBoxFor(model => model.LastName, new { maxlength = 50 })
#Html.ValidationMessageFor(model => model.LastName)
</div>
<div class="editor-label">
National number :
</div>
<div class="editor-field">
#Html.EditorFor(model => model.NumNat, new { maxlength = 11 })
#Html.ValidationMessageFor(model => model.NumNat)
</div>
<div class="editor-label">
Start date :
</div>
<div class="editor-field">
#Html.TextBoxFor(model => model.StartDate, new { #class = "datepicker", #Value = Model.StartDate.ToString("yyyy/MM/dd") })
#Html.ValidationMessageFor(model => model.StartDate)
</div>
<div class="editor-label">
End date :
</div>
<div class="editor-field">
#if (Model.EndDate.HasValue)
{
#Html.TextBoxFor(model => model.EndDate, new { #class = "datepicker", #Value = Model.EndDate.Value.ToString("yyyy/MM/dd") })
#Html.ValidationMessageFor(model => model.EndDate)
}
else
{
#Html.TextBoxFor(model => model.EndDate, new { #class = "datepicker" })
#Html.ValidationMessageFor(model => model.EndDate)
}
</div>
<div class="editor-label">
Distance House - Work (km) :
</div>
<div class="editor-field">
#Html.EditorFor(model => model.HouseToWorkKilometers)
#Html.ValidationMessageFor(model => model.HouseToWorkKilometers)
</div>
<div class="editor-label">
Category :
</div>
<div class="editor-field">
#Html.DropDownList("Id_ProductPackageCategory", "Choose one ...")
#Html.ValidationMessageFor(model => model.Id_ProductPackageCategory) <a href="../ProductPackageCategory/Create">
Add a new category?</a>
</div>
<div class="editor-label">
Upgrade? :
</div>
<div class="editor-field">
#Html.EditorFor(model => model.Upgrade)
#Html.ValidationMessageFor(model => model.Upgrade)
</div>
</div>
<div class="modal-footer">
<button class="btn btn-inverse" type="submit">Save</button>
</div>
}
Any idea on what's going on?

Try this first, just above #Html.ValidationSummary() in the partial view where you have the modal head, body and footer, place:
#Html.HiddenFor(model => model.PersonId) // or.Id whatever's in your model
This creates a hidden field in your view and sets model ID i.e. PK.

Fail to submit a list of object to the model binding using ICollection

i have added extra three input fields to my view to enable the system admin to submit four objects at the same time instead of one object at a time; the view looks as the following:-
#model Elearning.Models.Answer
#{
ViewBag.Title = "Create";
}
<div id = "partialWrapper">
#using (Ajax.BeginForm("Create", "Answer", new AjaxOptions
{
HttpMethod = "Post",
InsertionMode = InsertionMode.InsertAfter,
UpdateTargetId = "incrementanswer",
OnSuccess = "removePartial",
LoadingElementId = "progress2"
}))
{
<div id = "returnedquestion">
#Html.ValidationSummary(true)
<fieldset>
<legend>Answer here</legend>
<ol>
<li> <div class="editor-label">
#Html.LabelFor(model => model.Description)
</div>
<div class="editor-field">
#Html.TextBox("answer[0].Description")
#Html.ValidationMessageFor(model => model.Description)
</div>
<div class="editor-label">
#Html.LabelFor(model => model.IsRight)
</div>
<div class="editor-field">
#Html.DropDownList("IsRight", String.Empty)
#Html.ValidationMessageFor(model => model.IsRight)
</div>
</li>
<li> <div class="editor-label">
#Html.LabelFor(model => model.Description)
</div>
<div class="editor-field">
#Html.TextBox("answer[1].Description")
#Html.ValidationMessageFor(model => model.Description)
</div> <div class="editor-label">
#Html.LabelFor(model => model.IsRight)
</div>
<div class="editor-field">
#Html.DropDownList("IsRight", String.Empty)
#Html.ValidationMessageFor(model => model.IsRight)
</div> </li>
<li> <div class="editor-label">
#Html.LabelFor(model => model.Description)
</div>
<div class="editor-field">
#Html.TextBox("answer[2].Description")
#Html.ValidationMessageFor(model => model.Description)
</div> <div class="editor-label">
#Html.LabelFor(model => model.IsRight)
</div>
<div class="editor-field">
#Html.DropDownList("IsRight", String.Empty)
#Html.ValidationMessageFor(model => model.IsRight)
</div> </li>
<li> <div class="editor-label">
#Html.LabelFor(model => model.Description)
</div>
<div class="editor-field">
#Html.TextBox("answer[3].Description")
#Html.ValidationMessageFor(model => model.Description)
</div> <div class="editor-label">
#Html.LabelFor(model => model.IsRight)
</div>
<div class="editor-field">
#Html.DropDownList("IsRight", String.Empty)
#Html.ValidationMessageFor(model => model.IsRight)
</div> </li>
<ol>
</fieldset>
<input type= "hidden" name = "questionid" value = #ViewBag.questionid>
<input type= "hidden" name = "assessmentid" value = #ViewBag.assessmentid>
<input type="submit" value="Add answer" />
</div>
}
</div>
and the following Post Ation Method:-
[HttpPost]
public ActionResult Create(int questionid, ICollection<Answer> answer)
{
if (ModelState.IsValid)
{
foreach (var a in answer){
repository.AddAnswer(a);
repository.Save();
}
return PartialView("_details2",answer);
}
return View("_details2",answer);}
and last thing the _details2 partial view which contains the newly added objects:-
#model IEnumerable<Elearning.Models.Answer>
#{
ViewBag.Title = "Details";
}
#foreach (var m in Model)
{
<tr id = #m.AnswersID>
<td>
#Html.DisplayFor(modelItem => m.Description)
</td>
<td>
#*#Html.DisplayFor(modelItem => Model.Answer_Description.description)*#
#ViewBag.Answerdesription
</td>
<td>
#Ajax.ActionLink("Delete", "Delete", "Answer",
new { id = m.AnswersID },
new AjaxOptions
{
Confirm = "Are You sure You want to delete this Answer ?",
HttpMethod = "Post",
UpdateTargetId = #m.AnswersID.ToString(),
OnSuccess = "removePartial2"
})
</td>
</tr>
}
but the above is not working nethier the objects will be added nor the partial view will be returned , so how i can solve this issue???
BR

You bind your view to a single Elearning.Models.Answer object, how are you expecting to get a collection of Answers as a parameter in your Action? The default model binder will try to bind your view fields to the parameter in the Action but it won't be able to as it's a collection.
What you could try to do is to bind your View to a List<Elearning.Models.Answer> and feed it 4 empty Answer objects, then you can create a strongly typed Partial view that expects one Elearning.Models.Answer, add the Partial in a foreach and, when posting the form, expect that the default model binder does it work and fill your action method with a brand new List of Answer objects.
As an alternative, you can create a View Model object that contains the fields in your View, including those 4 description fields. You add them as Html.TextboxFor to bind each of them to a different property in the View Model. Then you can collect them in your action, provided you change it to public ActionResult Create(int questionid, ViewModelAnswer answer)
Does it make sense?

Your model should contain a list and code like this:
#for (int i=0; i < Model.FavouriteMovies.Count; i++) {
#Html.LabelFor(model => model.YourList[i].Field)
#Html.EditorFor(model => model.YourList[i].Field)
#Html.ValidationMessageFor(model => model.YourList[i].Field)
}
which will print something like:
<label for="YourList_0__Field">Field Name</label>
The Field Name field is required.
And receive the model back in your controller:
public ActionResult MyAction(MyModel model)
{
// First element?
model.YourList[0].
}

How to add data to both: Category id and Name Category from one Html.LabelFor?

In the view Create i want to add a new product. I need from the drop down list to select the category name. The problem is, that i have in the table Products add only the category id. And how me add and name too of category?
Structure my DB:
Table Brand: idbrand, name.
Table Make: idbrand, namebrand, idmake, name, price, urlmake.
I do the following:
// GET: /ShopManager/Create
public ActionResult Create()
{
ViewBag.BrandID = new SelectList(db.Brand, "BrandID", "Name");
return View();
}
//
// POST: /ShopManager/Create
[HttpPost]
public ActionResult Create(Make make)
{
if (ModelState.IsValid)
{
db.Make.AddObject(make);
db.SaveChanges();
return RedirectToAction("Index");
}
ViewBag.BrandID = new SelectList(db.Brand, "BrandID", "Name", make.BrandID);
return View(make);
}
#using (Html.BeginForm()) {
#Html.ValidationSummary(true)
<fieldset>
<legend>Марка телефона</legend>
<div class="editor-label">
#Html.LabelFor(model => model.BrandID, "Бренд")
</div>
<div class="editor-field">
#Html.DropDownList("BrandID", String.Empty)
#Html.ValidationMessageFor(model => model.BrandID)
</div>
<div class="editor-label">
#Html.LabelFor(model => model.Name, "Марка телефона")
</div>
<div class="editor-field">
#Html.EditorFor(model => model.Name)
#Html.ValidationMessageFor(model => model.Name)
</div>
<div class="editor-label">
#Html.LabelFor(model => model.Price, "Цена")
</div>
<div class="editor-field">
#Html.EditorFor(model => model.Price)
#Html.ValidationMessageFor(model => model.Price)
</div>
<div class="editor-label">
#Html.LabelFor(model => model.UrlMake, "Изображение")
</div>
<div class="editor-field">
#Html.EditorFor(model => model.UrlMake)
#Html.ValidationMessageFor(model => model.UrlMake)
</div>
<p>
<input type="submit" value="Создать" />
</p>
</fieldset>
<div>
#Html.ActionLink("Back to List", "Index")
</div>
How me add in Table Make BrandID and Name of Brand(name of Category)?

Since you have a Brand table it's not necessary to store brand's name in the Make also, you could get that with a simple join. Anyway if you really want to do that in the Create you can set it as the following code
make.NameBrand = db.Brand.Where(b => b.idbrand == make.idbrand).SingleOrDefault().namebrand;

MVC3 Passing Model to Controller - Receiving Null values

I just started working with MVC3 a few weeks ago and being young in the programming ladder I'm still learning quite a bit. I've recently been working with Models, using TextBoxFor and other helpers to populate properties for my "Character" Model.
Essentially what I'm trying to do is define a model and then pass it to my controller, however any property that I have defined as a static value in my Model is being passed as a null value on runtime.
Below are some snippets of the parts needed to understand whats going on..
Character.cs - Model
// Instances of manipulated objects.
otReal db = new otReal();
public player newPlayer = new player();
public byte[] conditions
{
get
{
return newPlayer.conditions;
}
set
{
byte[] array1 = null;
array1 = new byte[16 * 12 * 3];
newPlayer.conditions = array1;
}
}
CharacterController.cs
[AcceptVerbs(HttpVerbs.Post)]
public ActionResult Submit(Character c)
{
// Add a new character to the database via LINQ to Entities.
otReal.AddToplayers(c.newPlayer);
otReal.players.AddObject(c.newPlayer);
otReal.SaveChanges();
return View();
}
The only helpers I have in my View are the ones that the user actually needs to interact with. If I go into my controller and set the values there they will get set to the correct value and it will insert. Any help would be greatly appreciated!
Index.cshtml - View
#using (Ajax.BeginForm("Submit", new AjaxOptions { OnComplete = "done" }))
{
#Html.ValidationSummary(true)
<fieldset>
<legend>New Character Information</legend>
<div class="editor-label">
#Html.LabelFor(model => model.Name, "Character Name")
</div>
<div class="editor-field">
#Html.EditorFor(model => model.Name)
#Html.ValidationMessageFor(model => model.Name)
</div>
<div class="editor-label">
#Html.LabelFor(model => model.TownList)
</div>
<div class="editor-field">
#* #Html.DropDownList("TownList", ViewData["TownList"] as SelectList)*#
#Html.DropDownListFor(model => model.TownList, ViewData["TownList"] as SelectList)
#Html.ValidationMessageFor(model => model.TownList)
</div>
<div class="editor-label">
#Html.LabelFor(model => model.Sex)
</div>
<div class="editor-field">
#Html.DropDownListFor(model => model.Sex, ViewData["sex"] as SelectList)
#Html.ValidationMessageFor(model => model.Sex)
</div>
<div class="editor-label">
#Html.LabelFor(model => model.Vocation)
</div>
<div class="editor-field">
#Html.DropDownList("VocList", ViewData["VocList"] as SelectList)
#Html.ValidationMessageFor(model => model.Vocation)
</div>
<p>
<input id="button" type="submit" value="Create" />
</p>
<div style="font-family: Tahoma; font-size: large" id="completeDiv" style="display: none;">
</div>
<span></span>
</fieldset>
}
Basically what I'm trying to do here is create my model that has a bunch of base values that every 'Character' will have in the database table. This way when a player creates his/her character he/she will be able to enter a Character Name, Sex, Class(Vocation), Starting Town and all the other values will be populated behind the scenes and passed to the controller for creation.

Assuming you're trying to set values on 'newPlayer', then you can replace this
public player newPlayer = new player();
with this
public player newPlayer { get; set; }
The default model binder will create everything from the form on post-back--there's no need to instantiate it in the model.

Created a constructor for my model and inside the constructor I set the default values via the newly instantiated player model. Temp fix until I read into ataddeini's solution. Thanks everyone!