In a project how to set up a "client" console application and a "server" console application

Question

Alright so this might be worded wrong or using the wrong terminology. I want to know how I would set up a console application in my local machine that would be the "server" where it would run all my background tasks/events that happen on the client windows? I would only have one console application for the "server" and up to four "client" console applications.

Each of these would do separate things. The "server" application would just do all the calculations and functions and the client would just show in nice format what I want them to show from the results from the server.

Also I wouldn't know how to set it up in a C# type of project.

Answer 1

For a complete tutorial, I would recommend reading this Code Project article.

For some example code, the following client / server console applications are pulled from the MSDN.

Synchronous Client Socket Example:

using System;
using System.Net;
using System.Net.Sockets;
using System.Text;

public class SynchronousSocketClient {

    public static void StartClient() {
        // Data buffer for incoming data.
        byte[] bytes = new byte[1024];

        // Connect to a remote device.
        try {
            // Establish the remote endpoint for the socket.
            // This example uses port 11000 on the local computer.
            IPHostEntry ipHostInfo = Dns.Resolve(Dns.GetHostName())
            IPAddress ipAddress = ipHostInfo.AddressList[0];
            IPEndPoint remoteEP = new IPEndPoint(ipAddress,11000);

            // Create a TCP/IP  socket.
            Socket sender = new Socket(AddressFamily.InterNetwork, 
                SocketType.Stream, ProtocolType.Tcp );

            // Connect the socket to the remote endpoint. Catch any errors.
            try {
                sender.Connect(remoteEP);

                Console.WriteLine("Socket connected to {0}",
                    sender.RemoteEndPoint.ToString());

                // Encode the data string into a byte array.
                byte[] msg = Encoding.ASCII.GetBytes("This is a test<EOF>");

                // Send the data through the socket.
                int bytesSent = sender.Send(msg);

                // Receive the response from the remote device.
                int bytesRec = sender.Receive(bytes);
                Console.WriteLine("Echoed test = {0}",
                    Encoding.ASCII.GetString(bytes,0,bytesRec));

                // Release the socket.
                sender.Shutdown(SocketShutdown.Both);
                sender.Close();

            } catch (ArgumentNullException ane) {
                Console.WriteLine("ArgumentNullException : {0}",ane.ToString());
            } catch (SocketException se) {
                Console.WriteLine("SocketException : {0}",se.ToString());
            } catch (Exception e) {
                Console.WriteLine("Unexpected exception : {0}", e.ToString());
            }

        } catch (Exception e) {
            Console.WriteLine( e.ToString());
        }
    }

    public static int Main(String[] args) {
        StartClient();
        return 0;
    }
}

Synchronous Server Socket Example:

using System;
using System.Net;
using System.Net.Sockets;
using System.Text;

public class SynchronousSocketListener {

    // Incoming data from the client.
    public static string data = null;

    public static void StartListening() {
        // Data buffer for incoming data.
        byte[] bytes = new Byte[1024];

        // Establish the local endpoint for the socket.
        // Dns.GetHostName returns the name of the 
        // host running the application.
        IPHostEntry ipHostInfo = Dns.Resolve(Dns.GetHostName());
        IPAddress ipAddress = ipHostInfo.AddressList[0];
        IPEndPoint localEndPoint = new IPEndPoint(ipAddress, 11000);

        // Create a TCP/IP socket.
        Socket listener = new Socket(AddressFamily.InterNetwork,
            SocketType.Stream, ProtocolType.Tcp );

        // Bind the socket to the local endpoint and 
        // listen for incoming connections.
        try {
            listener.Bind(localEndPoint);
            listener.Listen(10);

            // Start listening for connections.
            while (true) {
                Console.WriteLine("Waiting for a connection...");
                // Program is suspended while waiting for an incoming connection.
                Socket handler = listener.Accept();
                data = null;

                // An incoming connection needs to be processed.
                while (true) {
                    bytes = new byte[1024];
                    int bytesRec = handler.Receive(bytes);
                    data += Encoding.ASCII.GetString(bytes,0,bytesRec);
                    if (data.IndexOf("<EOF>") > -1) {
                        break;
                    }
                }

                // Show the data on the console.
                Console.WriteLine( "Text received : {0}", data);

                // Echo the data back to the client.
                byte[] msg = Encoding.ASCII.GetBytes(data);

                handler.Send(msg);
                handler.Shutdown(SocketShutdown.Both);
                handler.Close();
            }

        } catch (Exception e) {
            Console.WriteLine(e.ToString());
        }

        Console.WriteLine("\nPress ENTER to continue...");
        Console.Read();

    }

    public static int Main(String[] args) {
        StartListening();
        return 0;
    }
}

To set this up, you would need to create a new solution in Visual Studio, and then add two console application projects to that solution, one for the client and one for the server. Once both projects are completed, you can copy and install the code provided above. Build the solution to generate a .exe file for both client and server. Locate your .exe files, run the server first, and then run the client second. You should see some output on both the server and client console windows.

EDIT: Please bear in mind that this will get you as far as running a server and client locally. When you distribute your server / client code to other machines, you will have to contend with firewalls, port forwarding, and potentially proxies depending on your network.