如何使用ASP.NET MVC DropDownListFor()发布选择列表值？

public class MyController : Controller
{
    public ActionResult Index()
    {
        var model = new MyModel();
        model.OptionList = new List<SelectListItem>
        {
            new SelectListItem { Value = "1", Text = "选项1" },
            new SelectListItem { Value = "2", Text = "选项2" },
            new SelectListItem { Value = "3", Text = "选项3" }
        };

        return View(model);
    }

    [HttpPost]
    public ActionResult Index(MyModel model)
    {
        // 执行所需的操作
        // model.PropertyName 包含选定的值

        return RedirectToAction("Index");
    }
}

@model MyModel

@using (Html.BeginForm())
{
    @Html.DropDownListFor(model => model.PropertyName, new SelectList(Model.OptionList, "Value", "Text"), "请选择")
    <input type="submit" value="提交" />
}

public class MyModel
{
    public string PropertyName { get; set; }
    public List<SelectListItem> OptionList { get; set; }
}