How can I extend MVC2 DropDownList/ListBox helpers to include custom attributes on the select option elements?

I'm stuck on what I thought was going to be a very simple task in ASP.Net MVC2.

I need to apply a background color to certain SELECT OPTION elements. To generate the dropdowns we're using the Html.DropDownList and Html.ListBox html helpers, and ideally I'd like to continue using these so I don't have to deal with re-binding the selected items from the form collection when the form is submitted and redisplayed.

For reasons I won't go into the Html helpers are called from within another html helper that we've written, so they're not in the view. The code looks like this...

var setOfOptions = question.AnswerList.Values.Select(x => new SelectListItem(){
                             Value = x.ID.ToString(),
                             Text = x.Caption + " - " + x.Style,
                             Selected = question.Answers.Contains((object)x.ID)
                        });
answerlistHtml = html.DropDownList(question.GetQualifiedId(), setOfOptions, "Please select...", new { @class = "superselect disabled" }).ToHtmlString();

So here we're turning a collection of our "AnswerListValue" objects into an IEnumerable, and generating SELECT html from that. However this gives me no way to get x.Style into the SELECT OPTION element - because there's no HtmlAttributes property on SelectListItem. Here's what I want the SELECT to look like...

<select id="whatever" name="whatever">
  开发者_如何学Python <option value="1" class="mystyle1">val1</option>
   <option value="2" class="mystyle2">val2</option>
   <option value="3" class="mystyle3">val3</option>
</select>

The obvious answer here is to make my own SelectListItemWithAttributes object - but I can't figure out how to create a DropDownListWithAttributes object, even after examining the MVC2 source code.

What would you do in this situation?

---

You would not need to 'create' your own DropDown helper. You would need to extend the default DropDown Helper. It`s pretty simple and thats the best thing about MVC.

I would suggest you check the answer of Creating a SelectListItem with the disabled="disabled" attribute to get an idea.