Error, multiple conections socket

I have this class i made with you help:

Client

Code:

---

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

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            IPAddress host = IPAddress.Parse("127.0.0.1");
            IPEndPoint hostep = new IPEndPoint(host, 10009);
            Socket sock = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);

            try
            {
                sock.Connect(hostep);
            }
            catch (SocketException e)
            {
                Console.WriteLine("Problem connecting to host");
                Console.WriteLine(e.ToString());
                sock.Close();
                return;
            }

            try
            {
              // sock.Send(Encoding.ASCII.GetBytes("testing"));
            }
            catch (SocketException e)
            {
                Console.WriteLine("Problem sending data");
                Console.WriteLine(e.ToString());
                sock.Close();
                return;
            }
        Console.ReadKey();
        }

    }
}

---

Server

Code:

---

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

namespace ServerSocket
{
    class Soquets
    {
        private static Socket Soquete;
        private static TcpListener tcpl = new TcpListener(IPAddress.Parse(IPAddress.Loopback.ToString()), 10009);
       
        public static string server_ip;
        public static Int32 porta;

        public static void Pause()
        {
            Console.ReadKey();
        }


        public static bool Iniciar()
        {
         
            User user;

            try
            {
                Soquete = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
                Soquete.Bind(new IPEndPoint(IPAddress.Parse(server_ip), porta));
                Soquete.Listen(1);
                Console.WriteLine(String.Format("Server online at ip {0}.",server_ip));
                try
                {
                    TcpClient ab;
                    Int32 usuarios = 0;
                    tcpl.Start();
                    Console.WriteLine(String.Format("Waiting for connections on port {0}.",porta));
                    while (true)
                    {

                        ab = tcpl.AcceptTcpClient();

                        user = new User(ab);
                        usuarios++;
                        user.ip = ((IPEndPoint)ab.Client.RemoteEndPoint).Address.ToString();

                        Console.WriteLine(String.Format("Client {0} connected -> IP: {1}", usuarios, user.ip));
                            try
                            {
                                byte[] buffer = new byte[4096];
                                int bytesReceived = user.ns.Read(buffer, 0, buffer.Length);
                                string message;
                                message = System.Text.Encoding.ASCII.GetString(buffer, 0, bytesReceived);
                                Console.WriteLine(String.Format("Received {0} from client {1}.", message, usuarios));
                            }
                            catch (Exception)
                            {
                                Console.WriteLine(String.Format("Client {0} disconeccted.", usuarios));
                                usuarios--;
                                return false;
                            }
                    }
                }

                catch (Exception ex)
                {
                    Console.WriteLine(ex.Message);
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
            }
            return true;
        }
    }
}

---

Its fine, when i connect: Client 1 connected... When i disconnect: Client 1 disconnected. Wel, when i try to reconect withou restarting server it does not show Client conected.

Where is the error?

My guess is that you should not return false in the catch block where you decrement your users counter.

Its worked, but, when i start server.exe, and run: client.exe it show, Client 1 connected, ip: 127.0.0.1. But if I open another client.exe nothing happend, and when i close the first client.exe it shows: client 1 disconnected, and suddenly appears: client 1 connected!

Was supposed to appear:
Client 1 connected
Client 2 connected
Received message "something" from Client 1
Client 2 Disconnected
Client 1 disconnected

Its just an example, but its not working >.<

And now the server.exe its not reading the message i send :S


@edit
wll, the error with not receiving the message i already fix it, but the error i said still remains ;s

Wel, the error was in Soquete.Listen(1). Error fixed. But now, when i do:

Code:

---

                    sock.Send(Encoding.ASCII.GetBytes("testing"));
                    Console.Write("Send testing\n");
                    Thread.Sleep(3000);
                    sock.Send(Encoding.ASCII.GetBytes("END"));
                    Console.Write("Send END\n");

---

The message END is not received !

I believe that TcpListener.AcceptTcpClient is a blocking method. I bet if you connect another client you will get the END message.

I dont understand you answer, i want to send several messages to server and the server must to receive all

In other words, the server will execute the first receive ("testing") and then it will go back to the top of the loop and execute:
ab = tcpl.AcceptTcpClient();

this will cause the server to wait until another connection is requested by a client. i.e. it blocks the execution of your program until it returns, but it won't return until a client requests a connection. You are probably going to need to asynchronously handle the connection logic.

i dont know whats is this, can you put this "asynchronously handl" into my loop, so I can understand what it is?

try adding this:

Code:

---

if(tcpl.Pending())
{
    ab = tcpl.AcceptTcpClient();
}

---

This is not asynchronous but it should fix your problem.

ok , i will try and then i post here the result.

Returns error:

br:
Referencia de objeto nao definida para uma instancia de objeto
eng:
Object reference not set to an instance of object

Does your loop look like this?

Code:

---

while (true)
{
                       
      if(tcpl.Pending())
      {
              ab = tcpl.AcceptTcpClient();
              user = new User(ab);
              usuarios++;
              user.ip = ((IPEndPoint)ab.Client.RemoteEndPoint).Address.ToString();

              Console.WriteLine(String.Format("Client {0} connected -> IP: {1}", usuarios, user.ip));
      }

     
                            try
                            {
                                byte[] buffer = new byte[4096];
                                int bytesReceived = user.ns.Read(buffer, 0, buffer.Length);
                                string message;
                                message = System.Text.Encoding.ASCII.GetString(buffer, 0, bytesReceived);
                                Console.WriteLine(String.Format("Received {0} from client {1}.", message, usuarios));
                            }
                            catch (Exception)
                            {
                                Console.WriteLine(String.Format("Client {0} disconeccted.", usuarios));
                                usuarios--;
                            }
                    }
                }

---

If i make like this, the prompt show error in line 88: 'use of unassigned local variable "user" '

I dont know if this will help you but if the client initiates the disconnect, the server will receive a no byte response (rather than a response with data in), this tells you that the client has disconnected. This should then prompt your code to close down that socket in the server and destroy it.

i dont understand what i can do to solve this problem