c# – .Net WebApi OData返回Queryable的操作

在该教程中,它被定义为：

[HttpPost]
public int RateProduct([FromODataUri] int key,ODataActionParameters parameters) 
{ 
    // ...
}

ODataModelBuilder modelBuilder = new ODataConventionModelBuilder();
modelBuilder.EntitySet<Product>("Products");

// New Code
ActionConfiguration rateProduct = modelBuilder.Entity<Product>().Action("RateProduct");
rateProduct.Parameter<int>("Rating");
rateProduct.Returns<int>();

但是,我有一个位置实体的用例,足够聪明地返回其周围的某个半径的其他位置.大概应该是这样的：

[HttpPost]
public IQueryable<Location> GetLocationsWithinRadius([FromODataUri] int key,ODataActionParameters parameters) 
{ 
    // Get the Location instance intended to be the center of the radius by using the key
    // Do a radius search around it using (int)parameters["radius"] as the radius
    // return the IQueryable<Location> of all location found within that radius
}

ODataModelBuilder modelBuilder = new ODataConventionModelBuilder();
modelBuilder.EntitySet<Location>("Locations");

// New Code
ActionConfiguration getLocations = modelBuilder.Entity<Location>().Action("GetLocationsWithinRadius");
getLocations.Parameter<int>("radius");
getLocations.Returns<IQueryable<Location>>();

我希望让这个工作,当前的返回类型是IQueryable< Location>当前它不起作用.如果返回类型是一个像int的原始类型,那么它可以工作,否则当我在fiddler中创建一个帖子时,它会给出以下错误(该帖子类似于http：// localhost：2663 / odata / Locations(2112)/ GetLocationsWithinRadius请求正文为{radius：50})：

{
  "odata.error":{
    "code":"","message":{
      "lang":"en-US","value":"An error has occurred."
    },"innererror":{
      "message":"The 'ObjectContent`1' type failed to serialize the response body for content type 'application/json; odata=minimalmetadata; streaming=true; charset=utf-8'.","type":"System.InvalidOperationException","stacktrace":"","internalexception":{
        "message":"The related entity set could not be found from the OData path. The related entity set is required to serialize the payload.","type":"System.Runtime.Serialization.SerializationException","stacktrace":"   at System.Web.Http.OData.Formatter.Serialization.ODataFeedSerializer.WriteObject(Object graph,ODataMessageWriter messageWriter,ODataSerializerContext writeContext)rn   at System.Web.Http.OData.Formatter.ODataMediaTypeFormatter.<>c__DisplayClassa.<WriteToStreamAsync>b__9()rn   at System.Threading.Tasks.TaskHelpers.RunSynchronously(Action action,CancellationToken token)"
      }
    }
  }
}

可以做我想要完成的工作吗？如果是,请问是否返回的IQueryable< Location>变得与odata paramaters …(那将是很好)

谢谢