WCF InvalidOperationException: A binding instance has already been associated to listen URI

Question

I'm a beginner of WCF and I'm studying in Essential WCF.

I encountered a problem when using ServiceContract NameSpace and Name. when I run the code, I catch a bellow InvalidOperationException. But I couldn't understand clearly.

A binding instance has already been associated to listen URI 'http://localhost:8080/NamespaceChange01'. If two endpoints want to share the same ListenUri, they must also share the same binding object instance. The two conflicting endpoints were either specified in AddServiceEndpoint() calls, in a config file, or a combination of AddServiceEndpoint() and config.

Does anyone knows how to avide the InvalidOperationException ?

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.ServiceModel;

namespace NamespaceChange01
{

    [ServiceContract(Name = "MyServiceName", Namespace = "http://ServiceNamespace")]
    public interface IBurgerMaster
    {
        [return: MessageParameter(Name = "myOutput")]
        [OperationContract(Name = "OperationName", Action = "OperationAction", ReplyAction = "ReplyActionName")]
        double GetStockPrice(string ticker);
    }

    [ServiceBehavior(Namespace = "http://MyService")]
    public class BurgerMaster : IBurgerMaster
    {

        public double GetStockPrice(string ticker)
        {
            return 100.99;
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            ServiceHost host = new ServiceHost(typeof(BurgerMaster));
            host.Open();
            Console.ReadLine();
            host.Close();
        }
    }
}

• app.config

  <?xml version="1.0" encoding="utf-8" ?>
  <configuration>
    <system.serviceModel>
      <services>
        <service name="NamespaceChange01.BurgerMaster" behaviorConfiguration="mexServiceBehavior">
          <host>
            <baseAddresses>
              <add baseAddress="http://localhost:8080/NamespaceChange01"/>
            </baseAddresses>
          </host>
          <endpoint name="basic" binding="basicHttpBinding" contract="NamespaceChange01.IBurgerMaster"/>
          <endpoint name="mex" binding="mexHttpBinding" contract="IMetadataExchange"/>
        </service>
      </services>
      <behaviors>
        <serviceBehaviors>
          <behavior name="mexServiceBehavior">
            <serviceMetadata httpGetEnabled="true"/>
          </behavior>
        </serviceBehaviors>
      </behaviors>
    </system.serviceModel>
  </configuration>
  

Thanks.

Answer 1

Two endpoints (basic and mex) couldn't be on the same address. Add some specific address for one of them (or for both ones).

For example:

<endpoint name="mex" address="mex" binding="mexHttpBinding" contract="IMetadataExchange"/>