C# WCF REST 客户端 JSON 数组

本文关键字：JSON 数组 客户端 REST WCF | 更新日期: 2023-09-27 17:56:09

这里的例子（http://stackoverflow.com/questions/835839/client-configuration-to-consume-wcf-json-web-service）简单明了。 我创建了一个返回简单对象数组的 WCF RESTFUL JSON 服务。 在 JavaScript 中，我处理返回的内容没有问题，因此我的 Web 客户端工作正常。

我希望使此服务可从 Web 或 C# 客户端调用，以便公开的数据可以在多个上下文中使用，而无需复制获取数据的代码。

在我的 C# 代码中，我有代理客户端、接口协定和基于配置的绑定定义。 我在 C# 服务和 C# 客户端（用作测试验证工具的简单控制台应用）之间共享接口和数据代码模块。

在 C# 客户端上，不是数组形式的数据返回得很好。 一旦我让我的服务返回一个对象数组，无论是作为裸数组返回还是作为简单对象的包装属性，客户端的序列化程序就会静默失败并返回一个空数组。

这是我在顶层的客户端代码 

 // for managed code to call our Ajax/Json incident service, we need to reuse the interface contract, 
 // and use the ServiceModel.Channels infra to hand-code a proxy client.
 public class IncidentClient : ClientBase<IIncidentServices.IGetActiveIncidents>, IIncidentServices.IGetActiveIncidents
 {
    public incidents GetActiveIncidents(string environmentAbbreviation)
    {
        return base.Channel.GetActiveIncidents(environmentAbbreviation);
    }
 }
 class Program
 {
    static void Main(string[] args)
    {

        IncidentClient client = new IncidentClient();
        incidents data = client.GetActiveIncidents("prod");
        Console.Write("Call to GetActiveIncidents returned ");
        if (null == data)
        {
            Console.WriteLine("no data (null)");
        }
        else
        {
            Console.WriteLine(data.incidentList.Count.ToString() + " rows of incident data.");
        }
        Console.WriteLine("'nPress any key to continue...");
        Console.ReadLine();
    }
 }
}

当代码运行时，它总是告诉我有零行，调试器告诉我返回一个空数组。 我已经通过激活日志记录跟踪了与 WCF 跟踪工具交换的消息，并且我可以看到我的数据返回（数组中有 100 个元素。

棘手的部分是序列化程序只是默默地丢弃数据 - 这让我想知道我是否应该放弃基于 WCF 客户端库的代理并使用原始 HTTP get 和一个单独的 JSON 解析器来处理数据。

我的数据协定如下所示：

using System;
using System.Collections.Generic;
using System.Runtime.Serialization;
namespace Dan.Test.Incident.Data
{
[DataContract(Name="incidents", Namespace="Dan.Test.Incident.Data")]
public class incidents
{
    public incidents()
    {
            data = new List<incidentData>();
    }
    [DataMember(Name="incidentList")]
    private List<incidentData> data;
    [IgnoreDataMember]
    public List<incidentData> incidentList
    {
        get {
            if (null == data)
            {
                data = new List<incidentData>();
            }
            return data;
        }
    }
}
[DataContract(Name="incidentData", Namespace="Dan.Test.Incident.Data")]
[Serializable]
public class incidentData
{
    // define incident members and accessors for read-only get operations
    [DataMember(Name = "irNumber")]
    private string m_irNumber = null;       // the incident identifier as IR12345, etc.
    [DataMember(Name = "title")]
    private string m_title = null;          // the title of the incident
    [DataMember(Name = "devname")]
    private string m_devname = null;      // list of team members who were engaged
    [DataMember(Name = "description")]
    private string m_description = null;    // description of the incident
    [DataMember(Name = "startdate")]
    private DateTime m_startdate;
    [DataMember(Name = "priority")]
    private int m_priority = 0;
    [DataMember(Name = "environmentID")]
    private int m_environmentID = 0;
    [DataMember(Name = "status")]
    private string m_status;
    [DataMember(Name = "enddate")]
    private DateTime m_enddate;
    public incidentData()
    {
    }
}
}

我的接口定义是

using Dan.Test.Incident.Data;
using System.Collections.Generic;
using System.ServiceModel;
using System.ServiceModel.Web;
namespace IIncidentServices
{
[ServiceContract(Namespace = "Dan.Test.Incident.Data")]
public interface IGetActiveIncidents
{
    [OperationContract]
    [WebGet(ResponseFormat = WebMessageFormat.Json, BodyStyle = WebMessageBodyStyle.WrappedRequest)]
    incidents GetActiveIncidents(string environmentAbbreviation);
}
}

我的配置很简单：

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<system.diagnostics>
    <sources>
        <source name="System.ServiceModel.MessageLogging" switchValue="Error,ActivityTracing">
            <listeners>
                <add type="System.Diagnostics.DefaultTraceListener" name="Default">
                    <filter type="" />
                </add>
                <add name="ServiceModelMessageLoggingListener">
                    <filter type="" />
                </add>
            </listeners>
        </source>
        <source propagateActivity="true" name="System.ServiceModel" switchValue="Verbose,ActivityTracing">
            <listeners>
                <add type="System.Diagnostics.DefaultTraceListener" name="Default">
                    <filter type="" />
                </add>
                <add name="ServiceModelTraceListener">
                    <filter type="" />
                </add>
            </listeners>
        </source>
    </sources>
    <sharedListeners>
        <add initializeData="c:'users'danro'documents'visual studio 2012'projects'gadgetactiveincidentservice'consoleapplication1'app_messages.svclog"
            type="System.Diagnostics.XmlWriterTraceListener, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"
            name="ServiceModelMessageLoggingListener" traceOutputOptions="Timestamp">
            <filter type="" />
        </add>
        <add initializeData="c:'users'danro'documents'visual studio 2012'projects'gadgetactiveincidentservice'consoleapplication1'app_tracelog.svclog"
            type="System.Diagnostics.XmlWriterTraceListener, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"
            name="ServiceModelTraceListener" traceOutputOptions="Timestamp">
            <filter type="" />
        </add>
    </sharedListeners>
</system.diagnostics>
<startup> 
    <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5" />
</startup>
<system.serviceModel>
<diagnostics>
  <messageLogging logEntireMessage="true" logMalformedMessages="true"
    logMessagesAtServiceLevel="true" logMessagesAtTransportLevel="true"
    maxMessagesToLog="3000" maxSizeOfMessageToLog="100000" />
  <endToEndTracing messageFlowTracing="true" />
</diagnostics>
<bindings>
  <webHttpBinding>
    <binding name="NewBinding2" openTimeout="00:05:00" receiveTimeout="00:50:00"
      sendTimeout="00:05:00" hostNameComparisonMode="WeakWildcard"
      maxBufferSize="2000000" maxBufferPoolSize="2000000" maxReceivedMessageSize="2000000"
      useDefaultWebProxy="false" contentTypeMapper="">
      <readerQuotas maxDepth="32" maxStringContentLength="100000" maxArrayLength="10000"
        maxBytesPerRead="2000000" maxNameTableCharCount="100000" />
    </binding>
  </webHttpBinding>
</bindings>
<behaviors>
  <endpointBehaviors>
    <behavior name="webwcf">
      <webHttp defaultBodyStyle="WrappedRequest" defaultOutgoingResponseFormat="Json" 
        automaticFormatSelectionEnabled="true" faultExceptionEnabled="true" />
    </behavior>
  </endpointBehaviors>
</behaviors>
<client>
  <endpoint address="http://localhost/GadgetActiveIncidentService/ActiveIncidentService.svc"
    behaviorConfiguration="webwcf" binding="webHttpBinding" bindingConfiguration="NewBinding2"
    contract="IIncidentServices.IGetActiveIncidents" name="ActiveIncidentService" />
</client>
</system.serviceModel>
</configuration>

查看我的数据，这是返回内容的简短片段 - 唯一看起来奇怪的是数据中的 [d] __type行...... 

{"d":[{"__type":"incidentData:Dan.Test.Incident.Data",
"description":"My description","devname":"",
"enddate":"'/Date(1357995120000-0800)'/",
"environmentID":10,"irNumber":"IR742989","priority":1,
"startdate":"'/Date(1357973873643-0800)'/",
"status":"closed","title":"A subset of users "},
{"__type":"incidentData:Dan.Test.Incident.Data","description":"second description.",
"devname":"","enddate":"'/Date(1352871180000-0800)'/",
"environmentID":10,"irNumber":"IR595320","priority":2,
"startdate":"'/Date(1352758680000-0800)'/",
"status":"This incident has been downgraded.",
"title":"Users will be unable to upgrade"}]}

希望这里有人能阐明我需要做些什么才能使这项工作:)

提前致谢

担

C# WCF REST 客户端 JSON 数组

WCF 有两种现成的行为用于启用 JSON 数据：WebScriptEnablingBehavior（如果通过配置，则<enableWebScript/>）和WebHttpBehavior（相当于 <webHttp/>）。前者在使用 ASP.NET AJAX框架时使用，它在JS中为您提供了一个知道如何与服务通信的"代理"。后者用于更通用的JSON通信（比Web脚本的开销更少）。

根据您的评论，您正在使用第一个。该行为基于 ASP.NET AJAX框架的要求，必须将响应包装在一个对象中（您看到的{"d":...}事物），IIRC以防止某种JS原型劫持数组。因此，如果你想使用来自这样一个端点的JSON，你需要"解包"响应，去掉那个"d"，或者使用一个真正理解它的行为。

如果要使用"常规"HTTP 客户端使用服务，然后使用 JSON 序列化程序反序列化响应，最简单的方法是简单地创建一个包装类，然后将该类作为序列化程序的根类型传递，而不是 Incidents 类。如果您只有一个（或几个）类，这是一个简单的解决方案，但如果有很多类，它可能会成为维护问题。

如果要使用基于 WCF 的客户端使用服务，则需要确保使用与服务中使用的行为相同的行为 - WebScriptEnablingBehavior，而不是更常见的 WebHttpBehavior。那也将奏效。

如果您拥有该服务，还有另一种选择。您可以添加另一个端点，这次使用 WebHttpBehavior，它将返回数据而不使用包装"d"。这样，您应该能够直接使用 HTTP 客户端和反序列化程序。

下面的代码显示了前两个替代方法。

public class Post_e5cb2f0a_717d_4255_9142_7c9f7995fa4f
{
    [ServiceContract]
    public interface IGetActiveIncidents
    {
        [OperationContract]
        [WebGet(ResponseFormat = WebMessageFormat.Json, BodyStyle = WebMessageBodyStyle.WrappedRequest)]
        Incidents GetActiveIncidents(string environmentAbbreviation);
    }
    [CollectionDataContract]
    public class Incidents : List<IncidentData>
    {
        public Incidents() { }
        public Incidents(List<IncidentData> incidents) : base(incidents) { }
    }
    public class Service : IGetActiveIncidents
    {
        public Incidents GetActiveIncidents(string environmentAbbreviation)
        {
            Incidents incidents = new Incidents();
            incidents.Add(new IncidentData(
                "IR12345", "Title", "dev engaged", "description", DateTime.UtcNow, 1, 10, "status", DateTime.UtcNow + new TimeSpan(1, 0, 0, 0)));
            return incidents;
        }
    }
    [DataContract]
    public class IncidentData
    {
        public IncidentData(string irNumber, string title, string devName, string description, DateTime startDate, int priority, int envId, string status, DateTime endDate)
        {
            m_irNumber = irNumber;
            m_title = title;
            m_devname = devName;
            m_description = description;
            m_startdate = startDate;
            m_priority = priority;
            m_environmentID = envId;
            m_status = status;
            m_enddate = endDate;
        }
        [DataMember(Name = "irNumber")]
        private string m_irNumber = null;
        [DataMember(Name = "title")]
        private string m_title = null;
        [DataMember(Name = "devname")]
        private string m_devname = null;
        [DataMember(Name = "description")]
        private string m_description = null;
        [DataMember(Name = "startdate")]
        private DateTime m_startdate;
        [DataMember(Name = "priority")]
        private int m_priority = 0;
        [DataMember(Name = "environmentID")]
        private int m_environmentID = 0;
        [DataMember(Name = "status")]
        private string m_status;
        [DataMember(Name = "enddate")]
        private DateTime m_enddate;
        public IncidentData()
        {
        }
    }
    [DataContract]
    class IncidentWrapper
    {
        [DataMember(Name = "d")]
        public Incidents Incidents { get; set; }
    }
    public static void Test()
    {
        string baseAddress = "http://" + Environment.MachineName + ":8000/Service";
        ServiceHost host = new ServiceHost(typeof(Service), new Uri(baseAddress));
        var endpoint = host.AddServiceEndpoint(typeof(IGetActiveIncidents), new WebHttpBinding(), "");
        endpoint.Behaviors.Add(new WebScriptEnablingBehavior());
        host.Open();
        Console.WriteLine("Host opened");
        //Using a "normal" HTTP client
        WebClient c = new WebClient();
        byte[] data = c.DownloadData(baseAddress + "/GetActiveIncidents?environmentAbbreviation=dd");
        MemoryStream ms = new MemoryStream(data);
        DataContractJsonSerializer dcjs = new DataContractJsonSerializer(typeof(IncidentWrapper));
        IncidentWrapper wrapper = (IncidentWrapper)dcjs.ReadObject(ms);
        Console.WriteLine("Using HttpClient/DCJS: {0}", wrapper.Incidents.Count);
        // Using a WCF client (with WebScriptEnablingBehavior
        ChannelFactory<IGetActiveIncidents> factory = new ChannelFactory<IGetActiveIncidents>(new WebHttpBinding(), new EndpointAddress(baseAddress));
        factory.Endpoint.Behaviors.Add(new WebScriptEnablingBehavior());
        IGetActiveIncidents proxy = factory.CreateChannel();
        Console.WriteLine("Using WCF client (with WSEB): {0}", proxy.GetActiveIncidents("dd").Count);
    }
}
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