Question

我正在尝试编写符合OpenSearch规范的OpenSearch Suggestion服务。

http://www.opensearch.org/Specifications/OpenSearch/Extensions/Suggestions

此规范要求服务返回JSON数组，第一个元素是字符串，以下元素是字符串数组。我可以通过返回一个字符串数组（string [] []）并让WCF将其序列化为JSON来获得它。但是，为了符合规范，我试图返回一个对象数组（object []），第一个是字符串，其余的是字符串数组（string []）。

每当我尝试返回对象数组时，它都不起作用，例如：

来自服务：

[AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Allowed)]
public class SuggestionService : ISuggestionService
{
    public object[] Search(string searchTerms)
    {
        SearchSuggestions = new object[4];
        SearchText = searchTerms;
        SearchSuggestions[0] = SearchText;
        Text = new string[10];
        Urls = new string[10];
        Descriptions = new string[10];

        // Removed irrelevant ADO.NET code
        while (searchResultReader.Read() && index < 10)
        {

            Text[index] = searchResultReader["Company"].ToString();
            Descriptions[index] = searchResultReader["Company"].ToString();
            Urls[index] = "http://dev.localhost/Customers/EditCustomer.aspx?id=" +
                          searchResultReader["idCustomer"];
            index++;
        }

        SearchSuggestions[1] = Text;
        SearchSuggestions[2] = Descriptions;
        SearchSuggestions[3] = Urls;
        return SearchSuggestions;
    }

    [DataMember]
    public string SearchText { get; set; }

    [DataMember]
    public string[] Text { get; set; }

    [DataMember]
    public string[] Descriptions { get; set; }

    [DataMember]
    public string[] Urls { get; set; }

    [DataMember]
    public object[] SearchSuggestions { get; set; }
}

这是整个界面：

[ServiceContract]
public interface ISuggestionService
{
    [OperationContract]
    [WebGet(UriTemplate = "/Search?q={searchTerms}",
        BodyStyle = WebMessageBodyStyle.Bare,
        ResponseFormat = WebMessageFormat.Json)]
    object[] Search(string searchTerms);
}

这会导致服务返回“错误324（net :: ERR_EMPTY_RESPONSE）：未知错误。”这是我唯一能得到的错误。

我无法使用对象数组存储一个字符串和三个数组吗？为了使用WCF返回符合此规范的正确JSON，我还能做些什么？

编辑：添加了更多代码

Answer 1

你发布了一堆[DataMember]的。请发布整个[DataContract]。同时向我们展示返回DataContract时返回的JSON。

数据合同不应包含行为。尝试以下（我没有机会测试它，并且需要假装数据来执行此操作）：

[AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Allowed)]
public class SuggestionService : ISuggestionService
{
    public SearchResults Search(string searchTerms)
    {
        var results = new SearchResults
                          {
                              SearchText = searchTerms,
                              Text = new string[10],
                              Urls = new string[10],
                              Descriptions = new string[10]
                          };

        // Removed irrelevant ADO.NET code
        int index = 0;
        while (searchResultReader.Read() && index < 10)
        {

            results.Text[index] = searchResultReader["Company"].ToString();
            results.Descriptions[index] = searchResultReader["Company"].ToString();
            results.Urls[index] = "http://dev.localhost/Customers/EditCustomer.aspx?id=" +
                          searchResultReader["idCustomer"];
            index++;
        }

        return results;
    }
}

[DataContract]
public class SearchResults
{
    [DataMember]
    public string SearchText { get; set; }

    [DataMember]
    public string[] Text { get; set; }

    [DataMember]
    public string[] Descriptions { get; set; }

    [DataMember]
    public string[] Urls { get; set; }
}

好的，我已经阅读了足够的规范和JSON规范，以说服自己确实需要返回一个对象数组，而不是一个包含对象数组的类的实例。当然，这并不是很有效。这就是你需要的：

[ServiceContract]
[ServiceKnownType(typeof(string))]
[ServiceKnownType(typeof(string[]))]
public interface ISuggestionService
{
    [OperationContract]
    [WebGet(UriTemplate = "/Search?q={searchTerms}",
        BodyStyle = WebMessageBodyStyle.Bare,
        ResponseFormat = WebMessageFormat.Json)]
    object[] Search(string searchTerms);
}

我刚刚尝试过它，它有效。这是JSON（添加了缩进）：

[
    "abc",
    ["Company1","Company2","Company3",...],
    ["Company1 Description","Company2 Description","Company3 Description",...],
    ["http:\/\/dev.localhost\/Customers\/EditCustomer.aspx?id=1",
     "http:\/\/dev.localhost\/Customers\/EditCustomer.aspx?id=2",
     "http:\/\/dev.localhost\/Customers\/EditCustomer.aspx?id=3",...]
]

Answer 2

这个问题让我感到困惑了一段时间 - 有一个完整的端到端演练如何执行此操作，包括如何支持JSON和XML opensearch（包括XML属性序列化），可下载代码，位于“Building Labs – Writing an OpenSearch Suggestions provider in C# with WCF”。

在WCF中将对象数组序列化为JSON以符合OpenSearch

2 个答案: