namespace Wcf.WinService
{
    public partial class CalService : ServiceBase
    {
        public ServiceHost serviceHost = null; //服务宿主

        public CalService()
        {
            InitializeComponent();
            base.ServiceName = "WCF.ServiceHostByWindowService";
        }

        protected override void OnStart(string[] args)
        {
           
            if(serviceHost != null)
            {
                serviceHost.Close();
            }
            serviceHost = new ServiceHost(typeof(Cal));
            serviceHost.Open();          
            base.OnStart(args);
        }

        protected override void OnStop()
        {
            if (serviceHost != null)
            {
                serviceHost.Close();
                serviceHost = null;
            }
            base.OnStop();
        }
    }
}

namespace Wcf.WinService
{
    [ServiceContract]
    public interface ICal
    {

        [OperationContract]
        int Add(int a, int b);

         [OperationContract]
        string GetValue(string value);

    }
}

namespace Wcf.WinService
{
    public class Cal : ICal
    {

        public int Add(int a, int b)
        {
            return a+b;
        }

        public string GetValue(string value)
        {
            return "hello " + value;
        }
    }
}

<?xml version="1.0" encoding="utf-8"?>
<configuration>
<system.serviceModel>
  <services>
    <service name="Wcf.WinService.Cal"  behaviorConfiguration="basicBehavior">
      <host>
        <baseAddresses>
          <add baseAddress="http://localhost:8999/CalService"/>
        </baseAddresses>
      </host>
      <endpoint address="http://localhost:8999/CalServices" 
                contract="Wcf.WinService.ICal" 
                binding="basicHttpBinding" />
    </service>
  </services>
  <behaviors>
    <serviceBehaviors>
      <behavior name="basicBehavior">
        <serviceMetadata httpGetEnabled="true" />
      </behavior>
    </serviceBehaviors>
  </behaviors>
</system.serviceModel>
</configuration>