WCF 服务不返回 JSON 中的完整对象

[OperationContract]
    public FareDataModel GetFareAndDistanceJson(string source, string destination, string country, string city)
    {
       return  FareManager.GetFare(source, destination, country, city);

    }

我的 svc 类中有上述方法。但这不能完全以 Json 格式发送数据。

 {
"d": {
    "__type": "FareDataModel:#MeterupAutoTaxiWebService",
    "Fares": [
        {
            "__type": "VehicleFare:#MeterupAutoTaxiWebService"
        }
    ]
}
}

但是当我将其作为字符串返回时，我以字符串的形式获取数据。我真的很想得到json。这是我的票价数据模型对象

 [DataContract]
    public class FareDataModel
    {
        public string SourceAddress;
        public string DestinationAddress;
        public int Duration;
        public int Distance;
        public string Error;
        [DataMember]
        public List<VehicleFare> Fares = new List<VehicleFare>();
    }

    [DataContract]
    public class VehicleFare
    {
        public string PhoneNo;
        public string Vehicle;
        public double Fare;
    }

我

尝试了其中一篇文章中解释的所有更改，但没有任何内容对我有用。当我通过修改我的代码以字符串返回时，如下所示

[OperationContract]
    public string GetFareAndDistanceJson(string source, string destination, string country, string city)
    {
       return new JavaScriptSerializer().Serialize(FareManager.GetFare(source, destination, country, city));
    }

我得到以下结果

    {
    "d": "{'"SourceAddress'":'"Majestic, Bangalore, Karnataka, India'",'"DestinationAddress'":'"Marathahalli Market, Bangalore, Karnataka, India'",'"Duration'":2475,'"Distance'":19872,'"Error'":null,'"Fares'":[{'"PhoneNo'":null,'"Vehicle'":'"Auto'",'"Fare'":238}]}"
}

我真的需要一个真正的 json 响应。

这是我的班级

[ServiceContract(Namespace = "")]
[AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Allowed)]
public class Service1
{

    [OperationContract]
    public string GetFareAndDistanceJson(string source, string destination, string country, string city)
    {
       return new JavaScriptSerializer().Serialize(FareManager.GetFare(source, destination, country, city));
    }
    // Add more operations here and mark them with [OperationContract]
}

请帮帮我。

我的网络配置

    <?xml version="1.0"?>
<!--
  For more information on how to configure your ASP.NET application, please visit
  http://go.microsoft.com/fwlink/?LinkId=169433
  -->
<configuration>
    <system.web>
        <compilation debug="true" targetFramework="4.0" />
    </system.web>
    <system.serviceModel>
        <services>
            <service name="MeterupAutoTaxiWebService.Service1">
                <endpoint address="" behaviorConfiguration="MeterupAutoTaxiWebService.Service1AspNetAjaxBehavior"
                    binding="webHttpBinding" contract="MeterupAutoTaxiWebService.Service1" />
            </service>
        </services>
        <behaviors>
            <endpointBehaviors>
                <behavior name="MeterupAutoTaxiWebService.Service1AspNetAjaxBehavior">
              <enableWebScript/>
                </behavior>
            </endpointBehaviors>
            <serviceBehaviors>
                <behavior name="">
                    <serviceMetadata httpGetEnabled="true" />
                    <serviceDebug includeExceptionDetailInFaults="true" />
                </behavior>
            </serviceBehaviors>
        </behaviors>
        <serviceHostingEnvironment aspNetCompatibilityEnabled="true"
            multipleSiteBindingsEnabled="true" />
    </system.serviceModel>
  <connectionStrings>
    <add name="MeterupAutoTaxiEntities" connectionString="metadata=res://*/MeterupTaxiAutoEntities.csdl|res://*/MeterupTaxiAutoEntities.ssdl|res://*/MeterupTaxiAutoEntities.msl;provider=System.Data.SqlClient;provider connection string=&quot;data source=localhost;initial catalog=MeterupAutoTaxi;integrated security=True;multipleactiveresultsets=True;App=EntityFramework&quot;" providerName="System.Data.EntityClient" />
  </connectionStrings>
</configuration>