更新oData中的导航属性WebAPI

Question

我正在使用WebAPI oData。要求是更新实体的导航属性。

public class Question 
{ 
    public int QuestionId { get; set; } 
    public string QuestionTitle { get; set; } 
    public string QuestionBody { get; set; } 
    public List<Response> Responses { get; set; } //navigation property 
} 

public class Response 
{ 
    public string ResponseId { get; set; } 
    public int QuestionId { get; set; } //fk 
    public string ResponseBody { get; set; } 
} 

现在，如果我使用下面的链接来获取它工作在ODATA的WebAPI的答复

GET - /的OData /问题（1）/响应----成功合作。 在控制器我添加了一个动作来处理此请求为：

public IQueryable<Response> GetResponses([FromODataUri] Guid key) 
{ 
    // 
} 

POST - /的OData /问题（1）/响应---- 这不是工作;错误 消息是：该服务不支持的格式“〜/ EntitySet的/关键码/导航”

我在控制器添加的方法的OData请求是：

public List<Responses> CreateResponses([FromODataUri] Guid key, List<Response> responses) 
{ 
    // 
} 

如何可以支持添加/更新oData中的导航属性WebAPI

Answer 1

您需要自定义路由约定来处理POST的导航属性。下面的代码，

// routing convention to handle POST requests to navigation properties. 
public class CreateNavigationPropertyRoutingConvention : EntitySetRoutingConvention 
{ 
    public override string SelectAction(ODataPath odataPath, HttpControllerContext controllerContext, ILookup<string, HttpActionDescriptor> actionMap) 
    { 
     if (odataPath.PathTemplate == "~/entityset/key/navigation" && controllerContext.Request.Method == HttpMethod.Post) 
     { 
      IEdmNavigationProperty navigationProperty = (odataPath.Segments[2] as NavigationPathSegment).NavigationProperty; 
      controllerContext.RouteData.Values["key"] = (odataPath.Segments[1] as KeyValuePathSegment).Value; // set the key for model binding. 
      return "PostTo" + navigationProperty.Name; 
     } 

     return null; 
    } 
} 

注册路由惯例，

var routingConventions = ODataRoutingConventions.CreateDefault(); 
routingConventions.Insert(0, new CreateNavigationPropertyRoutingConvention()); 
server.Configuration.Routes.MapODataRoute("odata", "", GetEdmModel(), new DefaultODataPathHandler(), routingConventions); 

完整的范例here。