第一种方法：

List<SelectListItem> statusItems = new List<SelectListItem>();
            statusItems.Add(new SelectListItem() { Text = "==全部==", Value = "0", Selected = "0" == status });
            statusItems.Add(new SelectListItem() { Text = "未完成", Value = "1", Selected = "1" == status });
            statusItems.Add(new SelectListItem() { Text = "已完成", Value = "2", Selected = "2" == status });

ViewBag.statusOptions = statusItems;

完成状态:
               @Html.DropDownList("Text",@ViewBag.statusOptions as IEnumerable<SelectListItem>, new { @id = "StatusID" })

第二种方法：

@Html.DropDownList("myList",new SelectList(new[]{"A","B"}),"Choose")

第三种方法：
List<SelectListItem> listItem = new List<SelectListItem>();
            listItem.Add(new SelectListItem() { Text = "是", Value = "1"});

listItem.Add(new SelectListItem() { Text = "否", Value = "0"});

ViewData["List"]=new SelectList(listItem,"Value","Text","");

@Html.DropDownList("List",ViewData["List"] as SelectList,"请选择")