C# &引用；没有支持的到SQL的转换；从linq语句中提取方法后

我有以下linq声明：

 public IEnumerable<EventModel> GetList(
     EnumEventCategory? category = null,
     EnumEventType? type = null)
 {
      var listDB = from e in this.DataContext.Event
          join i in this.DataContext.Identifier on e.ID equals i.ID
          orderby e.Deadline, e.ID descending
          select new EventModel
          {
           ID = i.ID,
           IdentifierStatus = i.IdentifierStatus,
           IdentifierType = i.IdentifierType,
           EventCategory = e.EventCategory,
           EventType = e.EventType,
          };

      if (category != null && category != EnumEventCategory.Unknown)
      {
        listDB = listDB.Where(x => x.EventCategory == category);
      }

      if (type != null && type != EnumEventType.Unknown)
      {
        listDB = listDB.Where(x => x.EventType == type);
      }

      return listDB;
 }

---

有什么想法吗？

（仔细检查后重新编写）没有，那不行，你必须选择新的。将该方法作为一个ctor添加到EventModel类中，它将开始工作。谢谢Alex。我试过了，但没用。

 public IEnumerable<EventModel> GetList(
     EnumEventCategory? category = null,
     EnumEventType? type = null)
 {
     var listDB = from e in this.DataContext.Event
                  join i in this.DataContext.Identifier on e.ID equals i.ID
                  orderby e.Deadline, e.ID descending
                  select EventModel(i, e);

      if (category != null && category != EnumEventCategory.Unknown)
      {
          listDB = listDB.Where(x => x.EventCategory == category);
      }

      if (type != null && type != EnumEventType.Unknown)
      {
          listDB = listDB.Where(x => x.EventType == type);
      }
      return listDB;
 }

private static EventModel EventModel(Identifier i, Event e)
{
    return new EventModel
    {
        ID = i.ID,
        IdentifierStatus = i.IdentifierStatus,
        IdentifierType = i.IdentifierType,
        EventCategory = e.EventCategory,
        EventType = e.EventType,
     };
 }