‫Message Header سفارشی در WCF

 [DataContract]
    public class ApplicationContext
    {
        [DataMember( IsRequired = true )]
        public string UserId
        {
            get {  return _userId; }
            set
            {
                _userId = value;
            }
        }
        private string _userId;      

        [DataMember( IsRequired = true )]
        public static ApplicationContext Current
        {
            get
            {
                return _current;
            }
            private set { _current = value; }
        }
        private static ApplicationContext _current;  





        public static void Register( ApplicationContext appContext )
        {
            Current = appContext;
            IsRegistered = true;
        }
    }

public class ClientMessageHeaderInspector<T> : IClientMessageInspector
    {
        private readonly T _vaccine;

        public ClientMessageHeaderInspector( T vaccine )
        {
            this._vaccine = vaccine;
        }

        public void AfterReceiveReply( ref Message reply, object correlationState )
        {
        }

        public object BeforeSendRequest( ref Message request, IClientChannel channel )
        {
            MessageHeader messageHeader = MessageHeader.CreateHeader( typeof( T ).Name, typeof( T ).Namespace, this._vaccine );
            request.Headers.Add( messageHeader );
            return null;
        }
    }

public class ApplicationContextMessageBehavior : IEndpointBehavior
    {
        ClientMessageHeaderInspector<ApplicationContext> inspector = null;

        public ApplicationContextMessageBehavior()
        {
            inspector = new ClientMessageHeaderInspector<ApplicationContext>( ApplicationContext.Current );
        }

        public void AddBindingParameters( ServiceEndpoint endpoint, BindingParameterCollection bindingParameters )
        {
        }

        public void ApplyClientBehavior( ServiceEndpoint endpoint, ClientRuntime clientRuntime )
        {
            clientRuntime.MessageInspectors.Add( inspector );
        }

        public void ApplyDispatchBehavior( ServiceEndpoint endpoint, EndpointDispatcher endpointDispatcher )
        {
        }

        public void Validate( ServiceEndpoint endpoint )
        {          
        }
    }

public class ServiceMapper<TChannel>
    {      
        internal static EndpointAddress EPAddress
        {
            get
            {
                return _epAddress;
            }
        }
        private static EndpointAddress _epAddress;

        public static TChannel CreateChannel( Binding binding, string uriBase, string serviceName, bool setCredential )
        {
            _epAddress = new EndpointAddress( String.Format( "{0}{1}", uriBase, serviceName ) );

            var factory = new ChannelFactory<TChannel>( binding, _epAddress );        
         
           ApplicationContext.Register( new ApplicationContext
            {
                UserId = Guid.NewGuid()
            } );  



            factory.Endpoint.Behaviors.Add( new ApplicationContextMessageBehavior() );

            TChannel proxy = factory.CreateChannel();

            if ( factory.Endpoint.Behaviors.OfType<ApplicationContextMessageBehavior>().Any() )
            {
                using ( var scope = new OperationContextScope( ( IClientChannel )proxy ) )
                {
                    OperationContext.Current.OutgoingMessageHeaders.Add( MessageHeader.CreateHeader( typeof( ApplicationContext ).Name, typeof( ApplicationContext ).Namespace, ApplicationContext.Current ) );
                }
            }

            return proxy;
        }

OperationContext.Current.OutgoingMessageHeaders.Add( MessageHeader.CreateHeader( typeof( ApplicationContext ).Name, typeof( ApplicationContext ).Namespace, AppConfiguration.Application ) );

 if ( OperationContext.Current != null && OperationContext.Current.IncomingMessageHeaders.FindHeader( typeof( ApplicationContext ).Name , typeof( ApplicationContext ).Namespace ) > 0 )
            {
                _application = OperationContext.Current.IncomingMessageHeaders.GetHeader<ApplicationContext>( typeof( ApplicationContext ).Name , typeof( ApplicationContext ).Namespace );
            }