htmlhelper dropdownlist selectlist to List <selectlist>

Question

我创建一个选择列表并将其设置为viewbag然后在视图中将其作为下拉列表拍摄..但它会引发此异常：

  

{“无法转换类型   'System.Collections.Generic.List＆LT; System.Web.Mvc.SelectListItem＆GT;'至   'System.Web.Mvc.SelectList'“}

这是我的控制器和html帮助器在视图中：

ViewBag.ProjeTipiList = valueSettingsService.GetRuzgarTurbunProjeTipiList().OrderBy(t => t.ProjeTipKod).ToSelectList(t => t.ProjeTipKod, t => t.Id.ToString(), "...Seçiniz...");

 @Html.DropDownListFor(model => model.ProjeTipId, (SelectList)ViewBag.ProjeTipiList, "Select One")

我该如何解决这个问题？

Answer 1

我会这样做：

ViewBag.ProjeTipiList = valueSettingsService.GetRuzgarTurbunProjeTipiList().OrderBy(t => t.ProjeTipKod).ToList();

@Html.DropDownListFor(model => model.ProjeTipId, new SelectList(ViewBag.ProjeTipiList,"ProjeTipKod","Id", "...Seçiniz...") ,"Select One")

Answer 2

因为DropDownList不接受字符串列表，所以它接受IEnumerable<SelectListItem>.

@Html.DropDownListFor(model => model.ProjeTipId, ((List<string>)ViewBag.ProjeTipiList).Select(m => new SelectListItem { Text = m, Value = m }))