Question

I have a few questions regarding WCF:
– Can a program act as both client and server ?
– What’s wrong with my code :

The service:

[ServiceContract]
public interface IShout
{
    [OperationContract]
    String Broadcast(String message);
}

The implementation:

public class eveShout : IShout
{
    public String Broadcast(String message)
    {
        return message + " reply";
    }
}

I start the service in the form contructor:

ServiceHost s = new ServiceHost(typeof(IShout));
s.AddServiceEndpoint(typeof(IShout), new BasicHttpBinding(), "http://localhost:9189");
s.Open();

The, When I click a button on another form, I want to send a message and get a reply back.
I use the following code:

ChannelFactory<IShout> channel = new ChannelFactory<IShout>(new BasicHttpBinding(), "http://localhost:9189");
IShout shout = channel.CreateChannel();

String reply = shout.Broadcast("Test");

Note: all the code is in the same namespace.
Note: I first start the “server” (open) then the app continues.

when i run the code, the server is created. I use netstat -a to see if the port is open. when I run the command, i get 9189 is in listening state. but the code stops at the command reply = shout(“test”). and I get anexception that says

The request channel timeout while waiting for a reply after 00:00:59…

Answer 1

Yes, you can have an app act as both client and server.

I see a couple of things that may need correcting. First, try adding OperationContract.

[ServiceContract]
public interface IShout
{
    [OperationContract]
    String Broadcast(String message);
} 

Then, take the type of the class, not the interface.

ServiceHost s = new ServiceHost(typeof(eveShout));
s.AddServiceEndpoint(typeof(IShout), new BasicHttpBinding(), "http://localhost:9189");
s.Open(); 

Make sure you you have permission to access the namespace (s.Open() should throw an exception if it does not).

net http add urlacl url=http://+:9189/ user=...

See if these suggestions help.

(oh yeh, and make Broadcast public in your class)

A quick example WindowsFormsApplication looks like this…

// form1.cs
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.ServiceModel;

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            ChannelFactory<IShout> channel = new ChannelFactory<IShout>(new BasicHttpBinding(), "http://localhost:9189");
            IShout shout = channel.CreateChannel();

            String reply = shout.Broadcast("Test"); 

        }
    }
}

// and Program.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Windows.Forms;
using System.ServiceModel;

namespace WindowsFormsApplication1
{
    static class Program
    {
        /// <summary>
        /// The main entry point for the application.
        /// </summary>
        [STAThread]
        static void Main()
        {
            ServiceHost s = new ServiceHost(typeof(eveShout));
            s.AddServiceEndpoint(typeof(IShout), new BasicHttpBinding(), "http://localhost:9189");
            s.Open(); 

            Application.EnableVisualStyles();
            Application.SetCompatibleTextRenderingDefault(false);
            Application.Run(new Form1());
        }
    }

    public class eveShout : IShout
    {
        public String Broadcast(String message)
        {
            return message + " reply";
        }
    } 

    [ServiceContract]
    public interface IShout
    {
        [OperationContract]
        String Broadcast(String message);
    } 
}

See if you can get something as simple as this working. That will at least prove to you that it can be done and that the problem is somewhere else.