无法将 net.tcp 添加为服务参考

Question

我已经像这样创建了一个 net.tcp WCF 服务：

const string tcpUri = "net.tcp://localhost:9038";
var netTcpHost = new WebServiceHost(typeof(DashboardService), new Uri(tcpUri));
netTcpHost.AddServiceEndpoint(typeof(IDashboardService), new NetTcpBinding(), 
                                                             "/dashboard");

netTcpHost.Open();

Console.WriteLine("Hosted at {0}. Hit any key to shut down", tcpUri);
Console.ReadKey();

netTcpHost.Close();

这是我的IDashboardService 和DashboardSerivce 定义：

[ServiceContract]
public interface IDashboardService
{
    [OperationContract]
    PositionDashboard Loader();
}

[ServiceBehavior(InstanceContextMode = InstanceContextMode.PerCall)]
public class DashboardService : IDashboardService
{
    public PositionDashboard Loader()
    {
        ...
    }
}

但是，当我尝试使用 WCF 测试客户端连接到服务时，我收到以下错误：

Error: Cannot obtain Metadata from net.tcp://localhost:9038/dashboard
The socket connection was aborted. This could be caused by an error processing your 
message or a receive timeout being exceeded by the remote host, or an underlying 
network resource issue. Local socket timeout was '00:04:59.9890000'.    An existing 
connection was forcibly closed by the remote host

Answer 1

错误明确提及 “无法获取元数据...”，因此值得检查您是否拥有 TCP Mex 端点。它在配置中应该是这样的：

<endpoint address="mex" binding="mexTcpBinding" contract="IMetadataExchange" />

或者，如果您想这样做，则需要参考 System.ServiceModel.Discovery，然后您的代码应如下所示：

const string tcpUri = "net.tcp://localhost:9038";
using (var netTcpHost = new WebServiceHost(
    typeof(DashboardService),
    new Uri(tcpUri)))
{
    netTcpHost.Description.Behaviors.Add(new ServiceMetadataBehavior());
    netTcpHost.AddServiceEndpoint(
        typeof(IMetadataExchange),
        MetadataExchangeBindings.CreateMexTcpBinding(),
        "mex");
    netTcpHost.AddServiceEndpoint(
        typeof(IDashboardService),
        new NetTcpBinding(),
        "dashboard");

    netTcpHost.Description.Behaviors.Add(new ServiceDiscoveryBehavior());
    netTcpHost.AddServiceEndpoint(new UdpDiscoveryEndpoint());

    netTcpHost.Open();
    Console.WriteLine("Hosted at {0}. Hit any key to shut down", tcpUri);
    Console.ReadLine();

    netTcpHost.Close();
}