C# 枚举转换selectlistitem 及 MVC @Html.DropDownListFor() 调用详细

枚举转换方法

        /// <summary>
        /// 根据枚举返回 List<SelectListItem>
        /// </summary>
        /// <param name="enumType"></param>
        /// <param name="withEmpty">true ---请选择--- </param>
        /// <param name="topValue">如果值不为0 则按枚举值选择</param>
        /// <returns></returns>
        public static List<SelectListItem> GetEnumDataSource(Type enumType, bool withEmpty, int topValue = 0)
        {
            List<SelectListItem> list = new List<SelectListItem>();

            if (withEmpty)
            {
                list.Add(new SelectListItem { Value = topValue.ToString(), Text = "--请选择--", Selected = true });
            }

            FieldInfo[] fields = enumType.GetFields();
            foreach (FieldInfo item in fields)
            {
                if (!item.FieldType.IsEnum)
                    continue;
                int value = (int)item.GetValue(null);
                if (value < 0)
                    continue;
                string text = string.Empty;
                object[] attrs = item.GetCustomAttributes(false);
                foreach (object attr in attrs)
                {
                    DescriptionAttribute des = attr as DescriptionAttribute;
                    if (des == null)
                    {
                        continue;
                    }
                    else
                    {
                        text = des.Description;
                    }
                }
                if (topValue == value)
                {
                    list.Add(new SelectListItem { Value = value.ToString(), Text = text, Selected = true });
                }
                else
                {
                    list.Add(new SelectListItem { Value = value.ToString(), Text = text });
                }
               
            }

            return list;
        }

Controller:

 var selectLists = EnumExtension.GetEnumDataSource(typeof(UserType), false, (int)result.Item.RoleId);
                TempData["RoleSalesList"] = selectLists;

View

@Html.DropDownListFor(model => model.RoleId , TempData["RoleSalesList"] as IEnumerable< SelectListItem>, new { @class = "form-control" } )