使用代码而不是配置文件将Message Inspector添加到WCF服务

Question

我通过Microsoft培训工具包（WCF）中的示例进行研究。它需要将“消息检查”添加到服务。

到目前为止，我已经创建了检查实现类，消息行为类和消息行为类扩展。

与其通过配置文件添加行为，不如将其添加到服务主机文件中。以下是实现类...

 public class MessageTrace : IDispatchMessageInspector
    {
        private Message TraceMessage(MessageBuffer buffer)
        {
            Message msg = buffer.CreateMessage();
            StringBuilder sb = new StringBuilder("Message content");
            sb.Append(msg.ToString());
            Console.WriteLine(sb.ToString());
            return buffer.CreateMessage();
        }

        public object AfterReceiveRequest(ref Message request, IClientChannel channel, InstanceContext instanceContext)
        {
            request = TraceMessage(request.CreateBufferedCopy(Int32.MaxValue));
            return null;
        }

        public void BeforeSendReply(ref Message reply, object correlationState)
        {
            reply = TraceMessage(reply.CreateBufferedCopy(Int32.MaxValue));
        }
    }

public class TraceMessageBehavior : IEndpointBehavior
    {
        public void AddBindingParameters(ServiceEndpoint endpoint, BindingParameterCollection bindingParameters)
        {}

        public void ApplyClientBehavior(ServiceEndpoint endpoint, ClientRuntime clientRuntime)
        {}

        public void ApplyDispatchBehavior(ServiceEndpoint endpoint, EndpointDispatcher endpointDispatcher)
        {
            MessageTrace inspector = new MessageTrace();
            endpointDispatcher.DispatchRuntime.MessageInspectors.Add(inspector);
        }

        public void Validate(ServiceEndpoint endpoint)
        {}
    }

 public class TraceMessageBehaviorExtension : BehaviorExtensionElement
    {
        public override Type BehaviorType
        {
            get { return typeof(TraceMessageBehavior); }
        }

        protected override object CreateBehavior()
        {
            return new TraceMessageBehavior();
        }
    }

Answer 1

您只能通过以下方式使用代码来实现。

1. 首先在服务类上使用属性。创建一个继承自IServiceBehavior的新属性。

   [AttributeUsage(AttributeTargets.Class)]
   public class TraceServiceBehavior : Attribute, IServiceBehavior
   {
   public void AddBindingParameters(ServiceDescription serviceDescription, ServiceHostBase serviceHostBase, System.Collections.ObjectModel.Collection<ServiceEndpoint> endpoints, BindingParameterCollection bindingParameters)
   {
   }
   
   public void ApplyDispatchBehavior(ServiceDescription serviceDescription, ServiceHostBase serviceHostBase)
   {
       foreach (ChannelDispatcher cDispatcher in serviceHostBase.ChannelDispatchers)
       {
           foreach (EndpointDispatcher eDispatcher in cDispatcher.Endpoints)
           {
               eDispatcher.DispatchRuntime.MessageInspectors.Add(new MessageTrace());
           }
       }
   }
   
   public void Validate(ServiceDescription serviceDescription, ServiceHostBase serviceHostBase)
   {
   }
   }
   

然后使用此属性装饰您的服务类

[TraceServiceBehavior]
public class Service1 : IService1
{
     // Methods
}

2. 创建从IServiceBehavior扩展的ServiceBehavior，与上面的代码相同，仅删除属性。

   公共类TraceServiceBehavior：IServiceBehavior {

   public void AddBindingParameters(ServiceDescription serviceDescription, ServiceHostBase serviceHostBase, System.Collections.ObjectModel.Collection<ServiceEndpoint> endpoints, BindingParameterCollection bindingParameters)
   {
   }
   
   public void ApplyDispatchBehavior(ServiceDescription serviceDescription, ServiceHostBase serviceHostBase)
   {
       foreach (ChannelDispatcher cDispatcher in serviceHostBase.ChannelDispatchers)
       {
           foreach (EndpointDispatcher eDispatcher in cDispatcher.Endpoints)
           {
               eDispatcher.DispatchRuntime.MessageInspectors.Add(new MessageTrace());
           }
       }
   }
   
   public void Validate(ServiceDescription serviceDescription, ServiceHostBase serviceHostBase)
   {
   }
   }
   

然后在ServiceHost中，以编程方式添加“行为”。

ServiceHost host = new ServiceHost(typeof(WcfService1.Service1));
            host.Description.Behaviors.Add(new WcfService1.TraceServiceBehavior());