How to enable tracing for WCF ajax enabled services?

How to enable tracing for WCF ajax enabled services? I have the following code:

 <system.diagnostics>
<sources>
  <source name="System.ServiceModel.MessageLogging">
    <listeners>
      <add name="messages"
      type="System.Diagnostics.XmlWriterTraceListener"
      initializeData="c:\logs\messages.svclog" />
    </listeners>
  </source>
</sources>
开发者_如何学JAVA

but it doesn't work.

thanks in advance.

Try like this:

<sources>
  <source name="System.ServiceModel"
          switchValue="Information, ActivityTracing"
          propagateActivity="true">
    <listeners>
      <add name="sdt"
          type="System.Diagnostics.XmlWriterTraceListener"
          initializeData="c:\logs\messages.svclog" />
    </listeners>
  </source>
</sources>