C# 如何正确扩展WebAPI 2 OData v4控制器以自动提供相关的实体集合

在我的WebAPI 2/Entity Framework 6/OData v4服务中，我有以下简单控制器：

public class InformationProductController : ODataController
    {
        GCIMContext db = new GCIMContext();

        protected override void Dispose(bool disposing)
        {
            db.Dispose();
            base.Dispose(disposing);
        }

        [EnableQuery]
        public IQueryable<InformationProduct> Get()
        {
            return db.InformationProducts;
        }
    }

DataEntity又有一个类型为

DataSource

的子实体集合：

public partial class DataEntity
    {
        public DataEntity()
        {
            this.PerformanceMetrics = new List<PerformanceMetric>();
            this.DataAttributes = new List<DataAttribute>();
            this.BusinessEntities = new List<BusinessEntity>();
            this.DataDeliveryChannels = new List<DataDeliveryChannel>();
            this.DataSources = new List<DataSource>();
            this.MasterDatas = new List<MasterData>();
            this.SourceTools = new List<SourceTool>();
            this.SubjectAreas = new List<SubjectArea>();
            this.Udms = new List<Udm>();
        }

        public int ID { get; set; }
        public string Name { get; set; }
        public string Description { get; set; }
        public Nullable<int> InformationProduct_ID { get; set; }
        public Nullable<int> BiMeasure_ID { get; set; }
        public Nullable<int> BiFact_ID { get; set; }
        public Nullable<int> BiDimension_ID { get; set; }
        public virtual BiDimension BiDimension { get; set; }
        public virtual BiFact BiFact { get; set; }
        public virtual BiMeasure BiMeasure { get; set; }
        public virtual InformationProduct InformationProduct { get; set; }
        public virtual ICollection<PerformanceMetric> PerformanceMetrics { get; set; }
        public virtual ICollection<DataAttribute> DataAttributes { get; set; }
        public virtual ICollection<BusinessEntity> BusinessEntities { get; set; }
        public virtual ICollection<DataDeliveryChannel> DataDeliveryChannels { get; set; }
        public virtual ICollection<DataSource> DataSources { get; set; }
        public virtual ICollection<MasterData> MasterDatas { get; set; }
        public virtual ICollection<SourceTool> SourceTools { get; set; }
        public virtual ICollection<SubjectArea> SubjectAreas { get; set; }
        public virtual ICollection<Udm> Udms { get; set; }
    }

此查询的结果是：

{
  "@odata.context":"http://10.0.0.4:8080/$metadata#InformationProduct","value":[
    {
      "ID":1,"Name":"ODM Dashboard","Description":"ODM Dashboard","Governance_ID":1,"PerformanceMetric_ID":1,"DataEntities":[
        {
          "ID":1,"Name":"Data Entity 1","Description":"Data Entity 1","InformationProduct_ID":1,"BiMeasure_ID":null,"BiFact_ID":null,"BiDimension_ID":1,"DataSources":[
            {
              "ID":40,"Category":"Service Performance","SourceSystemName":"Account Improvement Plan","SourceSystemOwner":null,"SourceSystemLocation":null,"SourceSystemTeam":null,"SourceSystemNetworkSegment":null,"SourceSystemOsType":null,"SourceDatabaseName":null,"SourceDatabaseType":null,"SourceDatabaseVersion":null,"BiFact_ID":null
            }
          ]
        }
      ]
    }
  ]
}

由于我找不到任何可以表示嵌套的

$expand

运算符的JavaScript库，我现在转向我的API，希望它提供

InformationModel

集合以及扩展的

DataEntities

集合，它将与自己扩展的

数据源

集合一起出现-与上面显示的查询完全相同

我的问题是：如果使用5.7版或更高版本，我应该使用什么语法来扩展IQueryable结果，以包括

数据实体

，及其

数据源

集合？

如果您使用的是5.7版或更高版本，那么您可以使用该属性注释

数据实体

和

数据源

属性。这将使客户机上不需要

$expand

：

GET http://10.0.0.4:8080/InformationProduct

---

我应该在DbContext:[AutoExpand]public DbSet DataEntities{get；set；}内或在其他地方应用AutoExpand吗？对数据模型中的属性使用

AutoExpand

；例如，在

InformationProduct

类的

DataEntities

属性上。

{
  "@odata.context":"http://10.0.0.4:8080/$metadata#InformationProduct","value":[
    {
      "ID":1,"Name":"ODM Dashboard","Description":"ODM Dashboard","Governance_ID":1,"PerformanceMetric_ID":1,"DataEntities":[
        {
          "ID":1,"Name":"Data Entity 1","Description":"Data Entity 1","InformationProduct_ID":1,"BiMeasure_ID":null,"BiFact_ID":null,"BiDimension_ID":1,"DataSources":[
            {
              "ID":40,"Category":"Service Performance","SourceSystemName":"Account Improvement Plan","SourceSystemOwner":null,"SourceSystemLocation":null,"SourceSystemTeam":null,"SourceSystemNetworkSegment":null,"SourceSystemOsType":null,"SourceDatabaseName":null,"SourceDatabaseType":null,"SourceDatabaseVersion":null,"BiFact_ID":null
            }
          ]
        }
      ]
    }
  ]
}

GET http://10.0.0.4:8080/InformationProduct