How do I bind to a List as a Property on a Model in MVC 3 Razor?

Question

I've got a model that looks something like this:

public class EditUserViewModel
    {
        public EditUserViewModel()
        {

        }
        public EditUserDataModel User { get; set; }
    }

With a backing object that looks like this:

public class EditUserDataModel
{
    public EditUserDataModel()
    {
        Roles = new List<UserRoleListDataModel>();
    }
    [DisplayName("First Name")]
    public string FirstName { get; set; }
    [DisplayName("Last Name")]
    public string LastName { get; set; }
    [DisplayName("Full Name")]
    public string FullName { get { return FirstName + " " + LastName; } }
    public List<UserRoleListDataModel> Roles { get; set; }
}

And UserRoleListDataModel looks like this:

public class UserRoleListDataModel
{
    public Guid Id { get; set; }
    public string RoleName { get; set; }
    public bool UserIsInRole { get; set; }
}

Then, in my Razor file, I am using the whole thing like so:

@foreach (var role in Model.User.Roles)
{
<tr>
    <td>@role.RoleName</td>
    <td>@Html.CheckBoxFor(x=>role.UserIsInRole)</td>
</tr>
}

The problem I'm having, is when I submit the form and hit my controller action, the Roles list is not populated on my new model.

Here is what the submit action on the controller looks like:

public ActionResult EditUser(EditUserViewModel model) // model.User.Roles is empty.
{
    // Do some stuff...
    return RedirectToAction("UserList");
}

Anyone have any suggestions?

Answer 1

Cris Carew was close, and got me on the right track.

@for (int i=0;i < Model.User.Roles.Count;i++)
{
    @Html.Hidden("User.Roles.Index", i)
    @Html.HiddenFor(x => x.User.Roles[i].RoleName)
    <tr>
        <td>@Html.DisplayFor(x => Model.User.Roles[i].RoleName)</td>
        <td>@Html.CheckBoxFor(x => Model.User.Roles[i].UserIsInRole)</td>
    </tr>
}