當(dāng)值在數(shù)組中時選定的MVC 5 Razor html.Drodown listfor集我正在用C#和.NET Framework4.6.1開發(fā)ASP.NETMVC 5應(yīng)用程序。我有這個View:@model MyProject.Web.API.Models.AggregationLevelConfViewModel[...]@Html.DropDownListFor(m => m.Configurations[0].HelperCodeType,  (SelectList)Model.HelperCodeTypeItems, new { id = "Configurations[0].HelperCodeType" })這個ViewModel是：public class AggregationLevelConfViewModel{     private readonly List<GenericIdNameType> codeTypes;     private readonly List<GenericIdNameType> helperCodeTypes;     public IEnumerable<SelectListItem> CodeTypeItems     {         get { return new SelectList(codeTypes, "Id", "Name"); }     }     public IEnumerable<SelectListItem> HelperCodeTypeItems     {         get { return new SelectList(helperCodeTypes, "Id", "Name"); }     }     public int ProductionOrderId { get; set; }     public string ProductionOrderName { get; set; }     public IList<Models.AggregationLevelConfiguration> Configurations { get; set; }     public AggregationLevelConfViewModel()     {         // Load CodeTypes to show it as a DropDownList         byte[] values = (byte[])Enum.GetValues(typeof(CodeTypes));         codeTypes = new List<GenericIdNameType>();         helperCodeTypes = new List<GenericIdNameType>();         for (int i = 0; i < values.Length; i++)         {             GenericIdNameType cType = new GenericIdNameType()             {                 Id = values[i].ToString(),                 Name = EnumHelper.GetDescription((CodeTypes)values[i])             };             if (((CodeTypes)values[i]) != CodeTypes.NotUsed)                 codeTypes.Add(cType);             helperCodeTypes.Add(cType);         }     }}但我不能把它放進去new SelectList(codeTypes, "Id", "Name");或new SelectList(helperCodeTypes, "Id", "Name");因為所選的值在Configurations數(shù)組：字段AggregationLevelConfiguration.CodeType和AggregationLevelConfiguration.HelperCodeType.我想我必須在視圖中設(shè)置選定的值，但是我不知道如何去做。如何設(shè)置選定的值？