Question

I’m making small program for socket communication in C#. Here’re my codes:
Client (data sender):

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net;
using System.Net.Sockets;

namespace Client
{
class Program
{
    static Socket sck; //vytvor socket
    static void Main(string[] args)
    {
        sck = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
        IPEndPoint localEndPoint = new IPEndPoint(IPAddress.Parse("127.0.0.1"), 1234); //nastav premennú loacalEndPoint na lokálnu ip a port 1234
        try  //Skús sa
        {
            sck.Connect(localEndPoint); // pripojiť

        }
        catch { //ak sa to nepodarí
            Console.Write("Unable to connect to remote ip end point \r\n"); //vypíš chybovú hlášku
            Main(args);
        }

        Console.Write("Enter text: ");
        string text = Console.ReadLine();
        byte[] data = Encoding.ASCII.GetBytes(text);
        sck.Send(data);
        Console.Write("Data sent!\r\n");
        Console.Write("Press any key to continue...");
        Console.Read();
        sck.Close();
    }
}
}

Server (data reciver):

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net;
using System.Net.Sockets;


namespace Server
{
class Program
{
    static byte[] Buffer { get; set; } //vytvor Buffer
    static Socket sck;

    static void Main(string[] args)
    {
        sck = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp); //vytvor Socket
        sck.Bind(new IPEndPoint(0, 1234));
        sck.Listen(80);
        Socket accepted = sck.Accept();
        Buffer = new byte[accepted.SendBufferSize];
        int bytesRead = accepted.Receive(Buffer);
        byte[] formatted = new byte[bytesRead]; //vytvor novú Array a jej dĺžka bude dĺžka priatých infomácii
        for(int i=0; i<bytesRead;i++){
            formatted[i] = Buffer[i]; //načítaj z Buffer do formatted všetky priate Bajty

        }
        string strData = Encoding.ASCII.GetString(formatted); //z ASCII hodnôt urob reťazec
        Console.Write(strData + "\r\n"); //vypíš data
        sck.Close(); //ukonči spojenie


    }
}

}
My problem is: In client program I’m sending data on port 1234 to local ip. But I cannot connect. I have tried port 80 and it has connected. So please, where’s my problem? How can I connect to everyone port? Please ignore comments in code and please help me.

Answer 1

You’re listening on port 80, that is the port your client program should connect to. The “1234” is the LOCAL port the server is bound to. Nothing is listening on that port.