如何从linq查询中选择多个值并显示为列表

Question

我想知道如何使用asp.net mvc c＃中的linq查询检索符合特定条件的值。如下面的代码所示，我使用过 然而，这似乎是检索它找到的第一个值，但是我希望检索匹配查询中指定条件的值。请记住，我已经声明了将该值保存为字符串的变量，但这使得无法检索值列表。我试图将选择行更改为select new { cas.Description, das.AssetInstanceID }).AsEnumerable;，但我收到错误消息“无法将方法组分配给隐式类型的局部变量”

 costCentreEntities = context.tbl_Organisation_CostCentre.Where(c => c.CostCentreID == userCostCentre && c.IsDeleted != true).OrderBy(c => c.CostCentreDesc);
                var deviceDescription = (from cas in context.tbl_Organisation_CostCentreAssetSIM
                join oc in context.tbl_Organisation_CostCentre
                on cas.CostCentreID equals oc.CostCentreID
                join das in context.tbl_Device_AssetSensor
                on cas.AssetInstanceID equals das.AssetInstanceID
                where das.ParentAssetInstanceID == null
                select new { cas.Description, das.AssetInstanceID }).FirstOrDefault();
                assetDescription = deviceDescription.Description;
                assetId = deviceDescription.AssetInstanceID;
               return costCentreEntities.ToList().Select(cc => new DeviceMetricItem(cc.CostCentreID, assetId, null, null, cc.ContractID, assetDescription, cc.CostCentreDesc, cc.tbl_Organisation_CostCentre1.Count)).ToList();

下面是我的dtos / class，其中我声明了保存所需值的变量，请注意描述和assetInstanceId变量，实际上应该能够保存一个或多个值，而不是只有一个< / p>

public DeviceMetricItem(int ? CostCentreID , int? AssetInstanceId,  int? ParentCostCentreId, int? classificationId,   int ? ContractID , string Description , string CostCentreDesc ,  int NoChildren = 0 )
        {
            costCentreId = CostCentreID.HasValue ?  CostCentreID.Value:0;
            assetInstanceId = AssetInstanceId.HasValue ? AssetInstanceId.Value : 0;
            parentCostCentreId = ParentCostCentreId.HasValue ? ParentCostCentreId.Value : 0; 
            classificationId = classificationId.HasValue? classificationId.Value:0; 
            ContractID = ContractID.HasValue ? ContractID.Value:0;
            description = Description;
            costCentreDesc = CostCentreDesc ?? string.Empty;
            noChildren = NoChildren ;
    }
    public int costCentreId { get; set; }
    public string costCentreDesc { get; set; }
    public int assetInstanceId { get; set; }
    public int parentCostCentreId { get; set; }
    public string description { get; set; }
    public int noChildren { get; set;}
    public int contractId { get; set; }