WCF服务返回HTTP 200头，然后超时而不返回任何内容

Question

我有一个Silverlight 4用户控件，它调用驻留在ASP.NET 4 Web应用程序中的WCF服务。

启用匿名访问web服务。 clientaccesspolicy.xml已准备好并且已成功下载。正确导航到服务器上的FieldITDbService.svc会提取服务元数据。

然而，当我尝试查看测试页面调用该WCF服务的Silverlight控件，服务本身返回：不返回数据

HTTP/1.1 200 OK 
Date: Thu, 22 Jul 2010 21:15:54 GMT 
Server: Microsoft-IIS/6.0 
X-Powered-By: ASP.NET 
X-AspNet-Version: 4.0.30319 
Content-Encoding: gzip 
Content-Length: 4409 
Cache-Control: private 
Content-Type: application/soap+msbin1 

然后超时。我很困惑。有谁知道为什么会发生这种情况，或者我可以如何更有效地进行调试？我跟踪记录服务，但日志中没有错误 - 根据日志，它正在工作。

这里的显示会发生什么的链接（来自Fiddler2）：http://imgur.com/VwgqS.png

下面是MainPage.xaml.cs中调用WebService的代码：

var webService = new FieldITDbServiceClient(); 
webService.ReadVAMDataCompleted += webService_ReadVAMDataCompleted; 
webService.ReadVAMDataAsync(); 
webService.CloseAsync(); 

这里是ClientConfig在Silverlight项目用来调用web服务：

<system.serviceModel> 
    <bindings> 
     <customBinding> 
      <binding name="CustomBinding_FieldITDbService"> 
       <binaryMessageEncoding /> 
       <httpTransport maxReceivedMessageSize="2147483647" maxBufferSize="2147483647" /> 
      </binding> 
     </customBinding> 
    </bindings> 
    <client> 
     <endpoint address="http://[ipofmyserverhere]/FieldIT/FieldITDBService.svc" 
      binding="customBinding" bindingConfiguration="CustomBinding_FieldITDbService" 
      contract="DbServiceRef.FieldITDbService" name="CustomBinding_FieldITDbService" /> 
    </client> 
</system.serviceModel> 

这是在实际WCF服务的代码，FieldITDbService.svc：

[ServiceContract(Namespace = "")] 
    [AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Required)] 
    public class FieldITDbService 
    { 
     [OperationContract] 
     public List<VAM> ReadVAMData() 
     { 
      List<VAM> allData = new List<VAM>(); 
      using(FieldITEntities dbContext = new FieldITEntities()) 
      { 
       allData.AddRange(dbContext.VAMs.ToList()); 
      } 
      return allData; 
     } 
    } 

这里是在纸幅的serviceModel部应用程式web.config文件：

<system.serviceModel> 
    <diagnostics> 
     <messageLogging maxMessagesToLog="100" 
      logEntireMessage="true" 
      logMessagesAtServiceLevel="true" 
      logMalformedMessages="true" 
      logMessagesAtTransportLevel="true"> 
     </messageLogging> 
    </diagnostics> 
    <behaviors> 
     <serviceBehaviors> 
     <behavior name=""> 
      <serviceMetadata httpGetEnabled="true" /> 
      <serviceDebug includeExceptionDetailInFaults="true" /> 
     </behavior> 
     </serviceBehaviors> 
    </behaviors> 
    <bindings> 
     <customBinding> 
     <binding name="FieldIT.FieldITDbService.customBinding0"> 
      <binaryMessageEncoding /> 
      <httpTransport /> 
     </binding> 
     </customBinding> 
    </bindings> 
    <serviceHostingEnvironment aspNetCompatibilityEnabled="true" 
     multipleSiteBindingsEnabled="true" /> 
    <services> 
     <service name="FieldIT.FieldITDbService"> 
     <endpoint address="" binding="customBinding" bindingConfiguration="FieldIT.FieldITDbService.customBinding0" 
      contract="FieldIT.FieldITDbService" /> 
     <endpoint address="mex" binding="mexHttpBinding" contract="IMetadataExchange" /> 
     </service> 
    </services> 
    </system.serviceModel> 

Answer 1

切换到客户机HTTP处理通过将线

WebRequest.RegisterPrefix("http://", WebRequestCreator.ClientHttp); 

在的MainPage（）构造立即解决此问题并适用于所有浏览器。我不知道为什么或如何，但我只是想接受它并继续前进。

http://msdn.microsoft.com/en-us/library/dd920295%28v=VS.95%29.aspx