@Html.DropDownList

    //后台 
    public ActionResult OrderAdd()

        {

            var items = new List<SelectListItem>()

            {

              (new SelectListItem(){Text = "男", Value = "Male"}),

              (new SelectListItem(){Text = "女", Value = "female"})

            };

            ViewBag.sexList = items;

            return View();

        }

//前端



//默认为空

@Html.DropDownList("sexList", ViewBag.sexList as  List<SelectListItem>,"")



//默认为第一个值，也就是 "男"

@Html.DropDownList("sexList", ViewBag.sexList as List<SelectListItem>)