WCF Rest Service不返回JSON数据。 但它适用于XML

Question

The service contract info is below Service Contract:

 [OperationContract]
    [FaultContract(typeof(DcCustomFaultMessage))]        
    [WebInvoke(Method="GET", ResponseFormat = WebMessageFormat.Json,
        BodyStyle = WebMessageBodyStyle.Wrapped,
        UriTemplate = "/GetCustomData")]
    List<DcCustomData> GetCustomData();

and the config details here Config:

<system.serviceModel>
<services>
  <service name="MyService" behaviorConfiguration="MyServiceBehavior">
    <endpoint address="" binding="webHttpBinding"  bindingConfiguration="MyServiceBinding" behaviorConfiguration="web" contract="IMyService"/>
  </service>     
</services>    
<behaviors>
  <serviceBehaviors>
    <behavior name="MyServiceBehavior">
      <serviceDebug includeExceptionDetailInFaults="True"/>
      <serviceTimeouts transactionTimeout="05:00:00"/>
      <dataContractSerializer maxItemsInObjectGraph="2147483646"/>
      <serviceMetadata httpGetEnabled="True"/>      
    </behavior>
  </serviceBehaviors>
  <endpointBehaviors>
    <behavior name="web" >
      <webHttp helpEnabled="true" automaticFormatSelectionEnabled="false" defaultOutgoingResponseFormat="Json" />
    </behavior>
  </endpointBehaviors>
</behaviors>
<standardEndpoints>
  <webHttpEndpoint>
    <standardEndpoint name="" helpEnabled="true" automaticFormatSelectionEnabled="false" defaultOutgoingResponseFormat="Json"/>
  </webHttpEndpoint>
</standardEndpoints>  
<bindings>
  <webHttpBinding>
    <binding name="MyServiceBinding">
      <security mode="None"/>
    </binding>
  </webHttpBinding>
</bindings>    
<serviceHostingEnvironment multipleSiteBindingsEnabled="true" />    
<diagnostics performanceCounters="All"/>    

When i debugged ,GetCustomData() returns list. but when i check it on browser returns nothing.. no error information. please help me

Answer 1

Please configure WCF Message logging and use svctraceviewer tool to see the actual error that probably is happening behind the scenes:

<configuration>
<system.diagnostics>
    <trace autoflush="true" />
    <sources>
      <source name="System.ServiceModel" switchValue="Information, ActivityTracing" propagateActivity="true">
        <listeners>
          <add name="wcfTraceListener" type="System.Diagnostics.XmlWriterTraceListener" initializeData="E:\Errors\WcfTrace.svclog" traceOutputOptions="DateTime" />
        </listeners>
      </source>
    </sources>
  </system.diagnostics>
 </configuration>

https://msdn.microsoft.com/en-us/library/ms731859%28v=vs.110%29.aspx