创建Azure媒体服务AccesPolicy返回200 OK并且没有可用信息

Question

我试图在azure媒体服务中列出我的内容的发布网址列表。 我读到第一步是创建一个Acces Policy。 在MSDN文档中，它表示我将获得带有Id和其他参数的201 Create响应或者301 Moved Permanently响应，因为我需要将请求重新发送到提供的新URL。 我的问题是我得到200 OK响应没有可用的信息：

{
  "d": {
    "EntitySets": [
      "AccessPolicies",
      "Locators",
      "ContentKeys",
      "ContentKeyAuthorizationPolicyOptions",
      "ContentKeyAuthorizationPolicies",
      "Files",
      "Assets",
      "AssetDeliveryPolicies",
      "AssetFilters",
      "IngestManifestFiles",
      "IngestManifestAssets",
      "IngestManifests",
      "StorageAccounts",
      "Tasks",
      "NotificationEndPoints",
      "Jobs",
      "TaskTemplates",
      "JobTemplates",
      "MediaProcessors",
      "EncodingReservedUnitTypes",
      "Operations",
      "StreamingEndpoints",
      "Channels",
      "Programs",
      "Filters"
    ]
  }
}

我的代码：

public void Create()
        {
            if (string.IsNullOrWhiteSpace(Name))
            {
                Name = Guid.NewGuid().ToString();
            }
            string accessPolicyCreateRequestPayloadFormat = @"{0} ""Name"": ""{1}"", ""DurationInMinutes"": ""{2}"", ""Permissions"":""{3}""  {4}";
            string requestBody = string.Format(CultureInfo.InvariantCulture, accessPolicyCreateRequestPayloadFormat, "{", Name, DurationInMinutes.TotalMinutes, (int)Permissions, "}");

            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(string.Format(CultureInfo.InvariantCulture, "{0}AccessPolicies", _context.WamsEndpoint));
            request.Method = HttpVerbs.Post;
            request.ContentType = RequestContentType.Json;
            request.Accept = RequestContentType.Json;
            request.Headers.Add(RequestHeaders.XMsVersion, RequestHeaderValues.XMsVersion);
            request.Headers.Add(RequestHeaders.Authorization, string.Format(CultureInfo.InvariantCulture, RequestHeaderValues.Authorization, _context.AccessToken));
            request.Headers.Add(RequestHeaders.DataServiceVersion, RequestHeaderValues.DataServiceVersion);
            request.Headers.Add(RequestHeaders.MaxDataServiceVersion, RequestHeaderValues.MaxDataServiceVersion);
            request.ContentLength = Encoding.UTF8.GetByteCount(requestBody);

            using (StreamWriter streamWriter = new StreamWriter(request.GetRequestStream()))
            {
                streamWriter.Write(requestBody);
            }


            using (var response = (HttpWebResponse)request.GetResponse())
            {
                switch (response.StatusCode)
                {
                    case HttpStatusCode.MovedPermanently:
                        _context.CheckForRedirection();
                        Create();
                        break;
                    case HttpStatusCode.Created:
                        using (Stream responseStream = response.GetResponseStream())
                        {
                            using (StreamReader streamReader = new StreamReader(response.GetResponseStream(), true))
                            {
                                var returnBody = streamReader.ReadToEnd();
                                JObject responseJsonObject = JObject.Parse(returnBody);
                                var d = responseJsonObject["d"];
                                Id = d.Value<string>("Id");
                                DurationInMinutes = TimeSpan.FromMinutes(d.Value<double>("DurationInMinutes"));
                                Permissions = (AccessPolicyPermission)d.Value<int>("Permissions");
                                Name = d.Value<string>("Name");
                                Created = d.Value<DateTime>("Created");
                                LastModified = d.Value<DateTime>("LastModified");
                            }
                        }
                        break;
                    default:
                        Console.WriteLine(response.StatusDescription);
                        break;
                }

            }
        }