I am trying to implement an Edit ViewModel for my Linq2SQL entity called Product. It has a foreign key linked to a list of brands.

Currently I am populating the brand list via ViewData and using DropDownListFor, thus:

<div class="editor-field">
    <%= Html.DropDownListFor(model => model.BrandId, (SelectList)ViewData["Brands"])%>
    <%= Html.ValidationMessageFor(model => model.BrandId) %>
</div>

Now I want to refactor the view to use a strongly typed ViewModel and Html.EditorForModel():

<% using (Html.BeginForm()) {%>
    <%= Html.ValidationSummary(true) %>

    <fieldset>
        <legend>Fields</legend>

        <%=Html.EditorForModel() %>

        <p>
            <input type="submit" value="Save" />
        </p>
    </fieldset>

<% } %>

In my Edit ViewModel, I have the following:

public class EditProductViewModel
{
    [HiddenInput]
    public int ProductId { get; set; }

    [Required()]
    [StringLength(200)]
    public string Name { get; set; }

    [Required()]
    [DataType(DataType.Html)]
    public string Description { get; set; }

    public IEnumerable<SelectListItem> Brands { get; set; }

    public int BrandId { get; set; }

    public EditProductViewModel(Product product, IEnumerable<SelectListItem> brands)
    {
        this.ProductId = product.ProductId;
        this.Name = product.Name;
        this.Description = product.Description;
        this.Brands = brands;
        this.BrandId = product.BrandId;
    }
}

The controller is setup like so:

public ActionResult Edit(int id)
{
    BrandRepository br = new BrandRepository();

    Product p = _ProductRepository.Get(id);
    IEnumerable<SelectListItem> brands = br.GetAll().ToList().ToSelectListItems(p.BrandId);

    EditProductViewModel model = new EditProductViewModel(p, brands);

    return View("Edit", model);
}

The ProductId, Name and Description display correctly in the generated view, but the select list does not. The brand list definitely contains data.

If I do the following in my view, the SelectList is visible:

<% using (Html.BeginForm()) {%>
    <%= Html.ValidationSummary(true) %>

    <fieldset>
        <legend>Fields</legend>

        <%=Html.EditorForModel() %>

        <div class="editor-label">
            <%= Html.LabelFor(model => model.BrandId) %>
        </div>
        <div class="editor-field">
            <%= Html.DropDownListFor(model => model.BrandId, Model.Brands)%>
            <%= Html.ValidationMessageFor(model => model.BrandId) %>
        </div>
        <p>
            <input type="submit" value="Save" />
        </p>
    </fieldset>

<% } %>

What am I doing wrong? Does EditorForModel() not generically support the SelectList? Am I missing some kind of DataAnnotation?

I can't seem to find any examples of SelectList usage in ViewModels that help. I'm truly stumped. This answer seems to be close, but hasn't helped.