如何从WCF返回HttpContext.Current.Cache？

public class CacheBehavior : IServiceBehavior
{
    public void AddBindingParameters(ServiceDescription serviceDescription, ServiceHostBase serviceHostBase, Collection<ServiceEndpoint> endpoints, BindingParameterCollection bindingParameters)
    {
    }

    public void ApplyDispatchBehavior(ServiceDescription serviceDescription, ServiceHostBase serviceHostBase)
    {
        foreach (ChannelDispatcher dispatcher in serviceHostBase.ChannelDispatchers)
        {
            foreach (EndpointDispatcher endpointDispatcher in dispatcher.Endpoints)
            {
                if (endpointDispatcher.DispatchRuntime != null)
                {
                    endpointDispatcher.DispatchRuntime.MessageInspectors.Add(new CacheMessageInspector());
                }
            }
        }
    }

    public void Validate(ServiceDescription serviceDescription, ServiceHostBase serviceHostBase)
    {
    }
}

public class CacheMessageInspector : IDispatchMessageInspector
{
    public object AfterReceiveRequest(ref Message request, IClientChannel channel, InstanceContext instanceContext)
    {
        // 在这里访问HttpContext.Current.Cache
        return null;
    }

    public void BeforeSendReply(ref Message reply, object correlationState)
    {
        // 在这里访问HttpContext.Current.Cache
    }
}

  <behaviors>
   <serviceBehaviors>
      <behavior>
       <CacheBehavior />
      </behavior>
    </serviceBehaviors>
  </behaviors>
</system.serviceModel>