C# Server/Client Socketing help.

I am working on developing a client server application that currently provides simple chat functionality. The server application appears to be working properly listening on one port for a TCP connection and another for UDP messages. But, when the client attempts a connection I get an error thrown that says "The requested address is not valid in its context.". The server is currently running on one machine while the client is running on another. I am using a Unity 3d scene to run the client as eventually I would like to use this to develop a multiplayer game. Here is the source code for what I have. I have been working on this issue for days now and could really use the help. Thank you.

Server Main:

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.Threading;
using System.Collections;
using System.Net.Sockets;

namespace AxiomTestServer_Alpha_0_02
{
public partial class mainForm : Form
{
static void Main()
{
Application.Run(new mainForm());
}

public mainForm()
{
InitializeComponent();
}

const int PORT_NUM = 65000;
private Hashtable clients = new Hashtable();
private TcpListener listener;
private Thread listenerThread;
private UdpClient transmitter = new UdpClient(65002);
private Thread transThread;


private void ConnectUser(string userName, UserConnection sender)
{
if (clients.Contains(userName))
{
ReplyToSender("REFUSE", sender);
}

else
{
sender.Name = userName;
UpdateStatus(sender.Name + " has joined the chat");
clients.Add(userName, sender);
ReplyToSender("JOIN", sender);
SendToClients("CHAT|" + sender.Name + " has joined the chat.", sender);
}
}

private void DisconnectUser(UserConnection sender)
{
UpdateStatus(sender.Name + " has left the chat.");
SendToClients("CHAT|" + sender.Name + " has left the chat.", sender);
clients.Remove(sender.Name);
}

private void ConnectionListen()
{
try
{
listener = new TcpListener(System.Net.IPAddress.Any, PORT_NUM);
listener.Start();

do
{
UserConnection client = new UserConnection(listener.AcceptTcpClient());
client.LineRecieved += new LineRecieve(OnLineRecieved);
UpdateStatus("Someone is attempting a login");

} while (true);
}
catch
{
}
}

private void OnLineRecieved(UserConnection sender, string data)
{
string[] dataArray;

dataArray = data.Split((char)124);

switch (dataArray[0])
{
case "CONNECT":
ConnectUser(dataArray[1], sender);
break;
case "CHAT":
SendChat(dataArray[1], sender);
break;
case "DISCONNECT":
DisconnectUser(sender);
break;
default:
//let the users know this message was sent wrong
break;
}

}

private void receiveUDP()
{
while (true)
{
System.Net.IPEndPoint ipep = new System.Net.IPEndPoint(System.Net.IPAddress.Any, 65002);
byte[] content = transmitter.Receive(ref ipep);

if (content.Length > 0)
{
string message = Encoding.ASCII.GetString(content);
string[] data = message.Split((char)124);

UserConnection sender = (UserConnection)clients[data[0]];
OnLineRecieved(sender, data[1]+ "|" + data[2]);
}
}
}

private void mainForm_Load(object sender, EventArgs e)
{
listenerThread = new Thread(ConnectionListen);
listenerThread.IsBackground = true;
listenerThread.Start();

transThread = new Thread(receiveUDP);
transThread.IsBackground = true;
transThread.Start();
UpdateStatus("Server Started");

}

private void SendToClients(string message, UserConnection sender)
{
UserConnection client;

foreach (DictionaryEntry entry in clients)
{
client = (UserConnection)entry.Value;

if (client.Name != sender.Name)
{
client.SendData(message);
}
}
}

private void SendChat(string message, UserConnection sender)
{
SendToClients("CHAT|" + sender.Name + ": " + message, sender);
UpdateStatus(sender.Name + ": " + message);
}

private void ReplyToSender(string message, UserConnection sender)
{
sender.SendData(message);
}

private void Broadcast(string message)
{
UserConnection client;

foreach (DictionaryEntry entry in clients)
{
client = (UserConnection)entry.Value;
client.SendData(message);
}
}

private void mainForm_FormClosing(object sender, FormClosingEventArgs e)
{
transThread.Abort();
listenerThread.Abort();
}

public void UpdateStatus(string message)
{
textBox1.AppendText(message + "\n");
}
}
}

UserConnection:

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

namespace AxiomTestServer_Alpha_0_02
{
public delegate void LineRecieve(UserConnection sender, string data);

public class UserConnection
{
const int READ_BUFFER_SIZE = 255;
private TcpClient client;
private byte[] readBuffer = new byte[READ_BUFFER_SIZE];
private string strName;
public IPEndPoint ipAdd;
private UdpClient trans;


public UserConnection(TcpClient client)
{
this.client = client;
ipAdd = (IPEndPoint)client.Client.RemoteEndPoint;
this.client.GetStream().BeginRead(readBuffer, 0, READ_BUFFER_SIZE, new AsyncCallback(StreamReciever), null);
}

public string Name
{
get
{
return strName;
}

set
{
strName = value;
}
}

public event LineRecieve LineRecieved;

public void SendData(string data)
{
trans = new UdpClient(65002);
byte[] dataArr = Encoding.ASCII.GetBytes(data);
trans.Send(dataArr, dataArr.Length, ipAdd);

}

public void StreamReciever(IAsyncResult ar)
{
int bytesRead;
string strMessage;

try
{
lock (client.GetStream())
{
bytesRead = client.GetStream().EndRead(ar);
}

strMessage = Encoding.ASCII.GetString(readBuffer, 0, bytesRead - 1);
LineRecieved(this, strMessage);

lock (client.GetStream())
{
client.GetStream().BeginRead(readBuffer, 0, READ_BUFFER_SIZE, new AsyncCallback(StreamReciever), null);
}
}
catch (Exception e)
{
}
}


}
}

Client Connection Class:

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

namespace Axiom_ClientConnection_0_01
{
public class Connector
{
const int READ_BUFFER_SIZE = 255;
const int TCP_PORT_NUMBER = 65000;
const int UDP_PORT_NUMBER = 65002;
private TcpClient connectionClient;
private UdpClient transmissionClient = new UdpClient();// = new UdpClient(UDP_PORT_NUMBER);
private byte[] readbuffer = new byte[READ_BUFFER_SIZE];
public string message = "";
public string result = "";
private string username;
IPEndPoint ipAddress;
Thread UDPListenerThread;

public Connector() { }

public string ConnectionAttempt(string ServeIP, string PlayUsername)
{
username = PlayUsername;

try
{

connectionClient = new TcpClient(ServeIP,TCP_PORT_NUMBER);
connectionClient.GetStream().BeginRead(readbuffer, 0, READ_BUFFER_SIZE, new AsyncCallback(DoRead), null);

Login(username);
ipAddress = (IPEndPoint)connectionClient.Client.RemoteEndPoint;
transmissionClient.Connect(ServeIP, UDP_PORT_NUMBER);
UDPListenerThread = new Thread(receiveUDP);
UDPListenerThread.IsBackground = true;
UDPListenerThread.Start();
return "Connection Succeeded";
}
catch(Exception ex) {
return (ex.Message.ToString() + "Connection Failed");
}
}

private void receiveUDP()
{
transmissionClient.Client.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReuseAddress, true);
while (true)
{
System.Net.IPEndPoint ipep = new System.Net.IPEndPoint(System.Net.IPAddress.Any, UDP_PORT_NUMBER);
byte[] content = transmissionClient.Receive(ref ipep);

if (content.Length > 0)
{
string message = Encoding.ASCII.GetString(content);
//string[] data = message.Split((char)124);

ProcessCommands(message);
}
}
}

public void Login(string username)
{
StreamWriter writer = new StreamWriter(connectionClient.GetStream());
writer.Write("CONNECT|" + username);
writer.Flush();
}

public void PktTest(string data)
{
SendData(username + "|CHAT|" + data);
}

public void Disconnect()
{
SendData("DISCONNECT");
UDPListenerThread.Abort();

connectionClient.Close();
transmissionClient.Close();
}


private void DoRead(IAsyncResult ar)
{
int BytesRead;
try
{
BytesRead = connectionClient.GetStream().EndRead(ar);
if (BytesRead < 1)
{
result = "DISCONNECTED";
return;
}

string message = Encoding.ASCII.GetString(readbuffer, 0, BytesRead);
ProcessCommands(message);

connectionClient.GetStream().BeginRead(readbuffer, 0, READ_BUFFER_SIZE, new AsyncCallback(DoRead), null);
}
catch { }
}


private void SendData(string data)
{
byte[] dataArr = Encoding.ASCII.GetBytes(data);
try
{
transmissionClient.Send(dataArr, dataArr.Length, ipAddress);
}
catch (Exception e)
{
}
}

private void ProcessCommands(string data)
{
string[] dataArr;

dataArr = data.Split((char)124);

switch (dataArr[0])
{
case "JOIN":
result = "You have joined the chat!";
break;
case "CHAT":
result = dataArr[1].ToString();
break;
case "REFUSE":
Login(username);
result = "Connection refused. Attempting another login.";
break;
case "BROAD":
result = "SERVER MESSAGE: " + dataArr[1].ToString();
break;
default:
result = "Server sent bad message waiting for retry";
break;
}
}

}
}

Unity Script for the Client connection:

using UnityEngine;
using System.Collections;
using Axiom_ClientConnection_0_01;
using System.Runtime.InteropServices;
using System.Security.Permissions;

public class LinkingClient : MonoBehaviour {

public Connector testing = new Connector();
string lastMessage = "";
public Transform PlayerCoord;

// Use this for initialization
void Start () {
Debug.Log(testing.ConnectionAttempt("192.168.11.7", System.Environment.MachineName).ToString());

if (testing.result != "")
{
//Debug.Log(testing.result);
}
}

// Update is called once per frame
void Update () {
if (Input.GetKeyDown("space"))
{
Debug.Log("space bar was pressed");
testing.PktTest("space bar was pressed");
}

if (testing.message != "JOIN")
{
if (testing.result != lastMessage)
{
Debug.Log(testing.result);
lastMessage = testing.result;
}
}

testing.PktTest(PlayerCoord.position[0] + ", " + PlayerCoord.position[1] + ", " + PlayerCoord.position[2]);
}

void OnApplicationQuit()
{
try { testing.Disconnect(); }
catch { }
}


}

Hi,

Welcome to the forum. Please use [code] and [/code] tags around your code snippets because it makes them easier to read.

Where does the error occur exactly (which line throws the exception)? I tried reading through to see if I could see anything specific, but with the large volume of text couldn't localized the problem.

This post may be useful: http://social.msdn.microsoft.com/for...-098e0f49cd5b/

Hope that helps a bit. Let us know which line generates the error (and repost code with the [code] and [/code] tags if you need further help.

Hi sorry about that here is the code. Sorry about the volume too. I understand that it is a lot, but I was unsure if the issue was simply with the client or if maybe I had made a mistake in my server design.

Server Main

Code:

---

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.Threading;
using System.Collections;
using System.Net.Sockets;

namespace AxiomTestServer_Alpha_0_02
{
    public partial class mainForm : Form
    {
        static void Main()
        {
            Application.Run(new mainForm());
        }

        public mainForm()
        {
            InitializeComponent();
        }

        const int PORT_NUM = 65000;
        private Hashtable clients = new Hashtable();
        private TcpListener listener;
        private Thread listenerThread;
        private UdpClient transmitter = new UdpClient(65002);
        private Thread transThread;


        private void ConnectUser(string userName, UserConnection sender)
        {
            if (clients.Contains(userName))
            {
                ReplyToSender("REFUSE", sender);
            }

            else
            {
                sender.Name = userName;
                UpdateStatus(sender.Name + " has joined the chat");
                clients.Add(userName, sender);
                ReplyToSender("JOIN", sender);
                SendToClients("CHAT|" + sender.Name + " has joined the chat.", sender);
            }
        }

        private void DisconnectUser(UserConnection sender)
        {
            UpdateStatus(sender.Name + " has left the chat.");
            SendToClients("CHAT|" + sender.Name + " has left the chat.", sender);
            clients.Remove(sender.Name);
        }

        private void ConnectionListen()
        {
            try
            {
                listener = new TcpListener(System.Net.IPAddress.Any, PORT_NUM);
                listener.Start();

                do
                {
                    UserConnection client = new UserConnection(listener.AcceptTcpClient());
                    client.LineRecieved += new LineRecieve(OnLineRecieved);
                    UpdateStatus("Someone is attempting a login");

                } while (true);
            }
            catch
            {
            }
        }

        private void OnLineRecieved(UserConnection sender, string data)
        {
            string[] dataArray;

            dataArray = data.Split((char)124);

            switch (dataArray[0])
            {
                case "CONNECT":
                    ConnectUser(dataArray[1], sender);
                    break;
                case "CHAT":
                    SendChat(dataArray[1], sender);
                    break;
                case "DISCONNECT":
                    DisconnectUser(sender);
                    break;
                default:
                    //let the users know this message was sent wrong
                    break;
            }
       
        }

        private void receiveUDP()
        {
            while (true)
            {
                System.Net.IPEndPoint ipep = new System.Net.IPEndPoint(System.Net.IPAddress.Any, 65002);
                byte[] content = transmitter.Receive(ref ipep);

                if (content.Length > 0)
                {
                    string message = Encoding.ASCII.GetString(content);
                    string[] data = message.Split((char)124);

                    UserConnection sender = (UserConnection)clients[data[0]];
                    OnLineRecieved(sender, data[1]+ "|" + data[2]);
                }
            }
        }

        private void mainForm_Load(object sender, EventArgs e)
        {
            listenerThread = new Thread(ConnectionListen);
            listenerThread.IsBackground = true;
            listenerThread.Start();

            transThread = new Thread(receiveUDP);
            transThread.IsBackground = true;
            transThread.Start();
            UpdateStatus("Server Started");

        }

        private void SendToClients(string message, UserConnection sender)
        {
            UserConnection client;

            foreach (DictionaryEntry entry in clients)
            {
                client = (UserConnection)entry.Value;

                if (client.Name != sender.Name)
                {
                    client.SendData(message);
                }
            }
        }

        private void SendChat(string message, UserConnection sender)
        {
            SendToClients("CHAT|" + sender.Name + ": " + message, sender);
            UpdateStatus(sender.Name + ": " + message);
        }

        private void ReplyToSender(string message, UserConnection sender)
        {
            sender.SendData(message);
        }

        private void Broadcast(string message)
        {
            UserConnection client;

            foreach (DictionaryEntry entry in clients)
            {
                client = (UserConnection)entry.Value;
                client.SendData(message);
            }
        }

        private void mainForm_FormClosing(object sender, FormClosingEventArgs e)
        {
            transThread.Abort();
            listenerThread.Abort();
        }

        public void UpdateStatus(string message)
        {
            textBox1.AppendText(message + "\n");
        }
    }
}

---

UserConnection Class:

Code:

---

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

namespace AxiomTestServer_Alpha_0_02
{
    public delegate void LineRecieve(UserConnection sender, string data);

    public class UserConnection
    {
        const int READ_BUFFER_SIZE = 255;
        private TcpClient client;
        private byte[] readBuffer = new byte[READ_BUFFER_SIZE];
        private string strName;
        public IPEndPoint ipAdd;
        private UdpClient trans;
        //IPEndPoint ipep = new IPEndPoint(IPAddress.Parse("127.0.0.1"),9050);
        //private Thread connectThread;

        public UserConnection(TcpClient client)
        {
            this.client = client;
            ipAdd = (IPEndPoint)client.Client.RemoteEndPoint;
            this.client.GetStream().BeginRead(readBuffer, 0, READ_BUFFER_SIZE, new AsyncCallback(StreamReciever), null);
        }
       
        public string Name
        {
            get
            {
                return strName;
            }

            set
            {
                strName = value;
            }
        }

        public event LineRecieve LineRecieved;

      public void SendData(string data)
        {
            trans = new UdpClient(65002);
            byte[] dataArr = Encoding.ASCII.GetBytes(data);
            trans.Send(dataArr, dataArr.Length, ipAdd);

        }

      public void StreamReciever(IAsyncResult ar)
      {
          int bytesRead;
          string strMessage;

          try
          {
              lock (client.GetStream())
              {
                  bytesRead = client.GetStream().EndRead(ar);
              }

              strMessage = Encoding.ASCII.GetString(readBuffer, 0, bytesRead - 1);
              LineRecieved(this, strMessage);

              lock (client.GetStream())
              {
                  client.GetStream().BeginRead(readBuffer, 0, READ_BUFFER_SIZE, new AsyncCallback(StreamReciever), null);
              }
          }
          catch (Exception e)
          {
          }
      }
       
     
    }
}

---

Client Class:

Code:

---

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

namespace Axiom_ClientConnection_0_01
{
    public class Connector
    {
        const int READ_BUFFER_SIZE = 255;
        const int TCP_PORT_NUMBER = 65000;
        const int UDP_PORT_NUMBER = 65002;
        private TcpClient connectionClient;
        private UdpClient transmissionClient = new UdpClient();// = new UdpClient(UDP_PORT_NUMBER);
        private byte[] readbuffer = new byte[READ_BUFFER_SIZE];
        public string message = "";
        public string result = "";
        private string username;
        IPEndPoint ipAddress;
        Thread UDPListenerThread;

        public Connector() { }

        public string ConnectionAttempt(string ServeIP, string PlayUsername)
        {
            username = PlayUsername;

            try
            {
               
                connectionClient = new TcpClient(ServeIP,TCP_PORT_NUMBER);
                connectionClient.GetStream().BeginRead(readbuffer, 0, READ_BUFFER_SIZE, new AsyncCallback(DoRead), null);

                Login(username);
                ipAddress = (IPEndPoint)connectionClient.Client.RemoteEndPoint;
                transmissionClient.Connect(ServeIP, UDP_PORT_NUMBER);
                UDPListenerThread = new Thread(receiveUDP);
                UDPListenerThread.IsBackground = true;
                UDPListenerThread.Start();
                return "Connection Succeeded";
            }
            catch(Exception ex) {
                return (ex.Message.ToString() + "Connection Failed");
            }
        }

        private void receiveUDP()
        {
            transmissionClient.Client.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReuseAddress, true);
            while (true)
            {
                System.Net.IPEndPoint ipep = new System.Net.IPEndPoint(System.Net.IPAddress.Any, UDP_PORT_NUMBER);
                byte[] content = transmissionClient.Receive(ref ipep);

                if (content.Length > 0)
                {
                    string message = Encoding.ASCII.GetString(content);
                    //string[] data = message.Split((char)124);

                    ProcessCommands(message);
                }
            }
        }

        public void Login(string username)
        {
            StreamWriter writer = new StreamWriter(connectionClient.GetStream());
            writer.Write("CONNECT|" + username);
            writer.Flush();
        }

        public void PktTest(string data)
        {
            SendData(username + "|CHAT|" + data);
        }

        public void Disconnect()
        {
            SendData("DISCONNECT");
            UDPListenerThread.Abort();
           
            connectionClient.Close();
            transmissionClient.Close();
        }


        private void DoRead(IAsyncResult ar)
        {
            int BytesRead;
            try
            {
                BytesRead = connectionClient.GetStream().EndRead(ar);
                if (BytesRead < 1)
                {
                    result = "DISCONNECTED";
                    return;
                }

                string message = Encoding.ASCII.GetString(readbuffer, 0, BytesRead);
                ProcessCommands(message);

                connectionClient.GetStream().BeginRead(readbuffer, 0, READ_BUFFER_SIZE, new AsyncCallback(DoRead), null);
            }
            catch { }
        }


        private void SendData(string data)
        {
            byte[] dataArr = Encoding.ASCII.GetBytes(data);
            try
            {
                transmissionClient.Send(dataArr, dataArr.Length, ipAddress);
            }
            catch (Exception e)
            {
            }
        }

        private void ProcessCommands(string data)
        {
            string[] dataArr;

            dataArr = data.Split((char)124);

            switch (dataArr[0])
            {
                case "JOIN":
                    result = "You have joined the chat!";
                    break;
                case "CHAT":
                    result = dataArr[1].ToString();
                    break;
                case "REFUSE":
                    Login(username);
                    result = "Connection refused.  Attempting another login.";
                    break;
                case "BROAD":
                    result = "SERVER MESSAGE: " + dataArr[1].ToString();
                    break;
                default:
                    result = "Server sent bad message waiting for retry";
                    break;
            }
        }

    }
}

---

Unity Script for Connection and testing. The error shows at line 15 of this file. Ill post the full error after the script.

Code:

---


using UnityEngine;
using System.Collections;
using Axiom_ClientConnection_0_01;
using System.Runtime.InteropServices;
using System.Security.Permissions;

public class LinkingClient : MonoBehaviour {

    public Connector testing = new Connector();
    string lastMessage = "";
    public Transform PlayerCoord;

        // Use this for initialization
        void Start () {
        Debug.Log(testing.ConnectionAttempt("192.168.11.7", System.Environment.MachineName).ToString());

        if (testing.result != "")
        {
            //Debug.Log(testing.result);
        }
        }
       
        // Update is called once per frame
        void Update () {
        if (Input.GetKeyDown("space"))
        {
            Debug.Log("space bar was pressed");
            testing.PktTest("space bar was pressed");
        }

        if (testing.message != "JOIN")
        {
            if (testing.result != lastMessage)
            {
                Debug.Log(testing.result);
                lastMessage = testing.result;
            }
        }

        testing.PktTest(PlayerCoord.position[0] + ", " + PlayerCoord.position[1] + ", " + PlayerCoord.position[2]);
        }

    void OnApplicationQuit()
    {
        try { testing.Disconnect(); }
        catch { }
    }


}

---

The error message is:

The requested address is not valid in its context.

UnityEngine.Debug:Log(Object)
LinkingClient:Start() (at Assets/LinkingClient.cs:15)

It points to the line "Debug.Log(testing.ConnectionAttempt("192.168.11.7", System.Environment.MachineName).ToString());"

Thanks again.

Maybe TCP and UDP are trying to bind to the same port? Can you change the port they use?

Also, for others joining the thread, there is another thread on this topic at: http://answers.unity3d.com/questions...in-its-co.html