为下拉asp.MVC选择列表

<select name="dropdown" id="dropdown">
    <option value="option1">Option 1</option>
    <option value="option2">Option 2</option>
    <option value="option3">Option 3</option>
</select>

public ActionResult Index()
{
    List<SelectListItem> options = new List<SelectListItem>
    {
        new SelectListItem { Value = "option1", Text = "Option 1" },
        new SelectListItem { Value = "option2", Text = "Option 2" },
        new SelectListItem { Value = "option3", Text = "Option 3" }
    };

    ViewBag.Options = options;

    return View();
}

@Html.DropDownList("dropdown", ViewBag.Options as List<SelectListItem>, "Select an option")