asp.net mvc HtmlHelperExt EnumDropDownList

 public static class HtmlHelperExt
     {
         public static MvcHtmlString EnumDropDownList<TEnum>(this HtmlHelper htmlHelper, string name, TEnum selectedValue)
         {
             IEnumerable<TEnum> values = Enum.GetValues(typeof (TEnum))
                 .Cast<TEnum>();

             IEnumerable<SelectListItem> items =
                 from value in values
                 select new SelectListItem
                 {
                     Text = value.ToString(),
                     Value = value.ToString(),
                     Selected = (value.Equals(selectedValue))
                 };

             return htmlHelper.DropDownList(
                 name,
                 items
                 );
         }

         public static MvcHtmlString EnumDropDownListFor<TModel, TEnum>(this HtmlHelper<TModel> htmlHelper,
             Expression<Func<TModel, TEnum>> expression)
         {
             ModelMetadata metadata = ModelMetadata.FromLambdaExpression(expression, htmlHelper.ViewData);
             IEnumerable<TEnum> values = Enum.GetValues(typeof (TEnum)).Cast<TEnum>();

             IEnumerable<SelectListItem> items =
                 values.Select(value => new SelectListItem
                 {
                     Text = value.ToString(),
                     Value = value.ToString(),
                     Selected = value.Equals(metadata.Model)
                 });

             return htmlHelper.DropDownListFor(
                 expression,
                 items
                 );
         }
     }

HtmlHelper