从 Silverlight 客户端使用 IIS 中托管的 WF 服务时出现问题

Question

我正在尝试从 Silverlight 客户端使用 IIS Express (xamlx) 中托管的 WF 服务。

我添加了服务引用，当我使用客户端代理时，我得到以下信息：

System.ServiceModel.CommunicationException was unhandled by user code
  Message=An error occurred while trying to make a request to URI 'http://localhost:52878/Workflows/PerformanceAppraisal/Exempt.xamlx'. This could be due to attempting to access a service in a cross-domain way without a proper cross-domain policy in place, or a policy that is unsuitable for SOAP services. You may need to contact the owner of the service to publish a cross-domain policy file and to ensure it allows SOAP-related HTTP headers to be sent. This error may also be caused by using internal types in the web service proxy without using the InternalsVisibleToAttribute attribute. Please see the inner exception for more details.
  StackTrace:
       at System.ServiceModel.AsyncResult.End[TAsyncResult](IAsyncResult result)
       at System.ServiceModel.Channels.ServiceChannel.EndCall(String action, Object[] outs, IAsyncResult result)
       at System.ServiceModel.ClientBase`1.ChannelBase`1.EndInvoke(String methodName, Object[] args, IAsyncResult result)
       at CompanyHR.ExemptPAService.ExemptPAClient.ExemptPAClientChannel.EndInitiatePerformanceAppraisal(IAsyncResult result)
       at CompanyHR.ExemptPAService.ExemptPAClient.CompanyHR.ExemptPAService.IExemptPA.EndInitiatePerformanceAppraisal(IAsyncResult result)
       at CompanyHR.ExemptPAService.ExemptPAClient.OnEndInitiatePerformanceAppraisal(IAsyncResult result)
       at System.ServiceModel.ClientBase`1.OnAsyncCallCompleted(IAsyncResult result)
  InnerException: System.Security.SecurityException
       Message=""
       StackTrace:
            at System.Net.Browser.AsyncHelper.BeginOnUI(SendOrPostCallback beginMethod, Object state)
            at System.Net.Browser.BrowserHttpWebRequest.EndGetResponse(IAsyncResult asyncResult)
            at System.ServiceModel.Channels.HttpChannelFactory.HttpRequestChannel.HttpChannelAsyncRequest.CompleteGetResponse(IAsyncResult result)
       InnerException: System.Security.SecurityException
            Message=Security error.
            StackTrace:
                 at System.Net.Browser.BrowserHttpWebRequest.InternalEndGetResponse(IAsyncResult asyncResult)
                 at System.Net.Browser.BrowserHttpWebRequest.<>c__DisplayClass5.<EndGetResponse>b__4(Object sendState)
                 at System.Net.Browser.AsyncHelper.<>c__DisplayClass4.<BeginOnUI>b__1(Object sendState)
            InnerException: 

当我添加服务引用时，我没有使用 http://localhost:52878/Workflows/PerformanceAppraisal/Exempt.xamlx

我使用了它的 https 版本。但它似乎正在使用这个网址。

我在 Visual Studio 2010 中使用 IIS Express。

Answer 1

错误消息非常清楚地表明无法找到 clientaccesspolicy.xml。这是在 Silverlight 应用程序运行时调用不同站点上的服务的结果。您没有提到 Silverlight 应用程序的 URL，但可能是使用 HTTPS 的情况，也可能是完全不同的站点。