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Async socket server with multiple clients

i have a problem i am unable to resolve as my c# knowledge is not very good.
I found some code on the internet and modified it according to my needs.
My problem is that when i send messages to clients only one receives the message, then the next message is received by another client and so on.
I want to send same message to all connected clients without losing any data.
Server
using System;
using System.Net.Sockets;
using System.Threading;
public class AsynchIOServer
{
static TcpListener tcpListener = new TcpListener(10);
static void Listeners()
{
Socket socketForClient = tcpListener.AcceptSocket();
if (socketForClient.Connected)
{
Console.WriteLine("Client:"+socketForClient.RemoteEndPoint+" now connected to server.");
NetworkStream networkStream = new NetworkStream(socketForClient);
System.IO.StreamWriter streamWriter =
new System.IO.StreamWriter(networkStream);
System.IO.StreamReader streamReader =
new System.IO.StreamReader(networkStream);
////here we send message to client
while (true){
Console.WriteLine("type your message to be recieved by client:");
string theString = Console.ReadLine();
streamWriter.WriteLine(theString);
////Console.WriteLine(theString);
streamWriter.Flush();
}
streamReader.Close();
networkStream.Close();
streamWriter.Close();
}
socketForClient.Close();
Console.WriteLine("Press any key to exit from server program");
Console.ReadKey();
}
public static void Main()
{
//TcpListener tcpListener = new TcpListener(10);
tcpListener.Start();
Console.WriteLine("************This is Server program************");
Console.WriteLine("Hoe many clients are going to connect to this server?:");
int numberOfClientsYouNeedToConnect =int.Parse( Console.ReadLine());
for (int i = 0; i < numberOfClientsYouNeedToConnect; i++)
{
Thread newThread = new Thread(new ThreadStart(Listeners));
newThread.Start();
}
}
}
Client:
using System;
using System.Net.Sockets;
using System.Threading;
public class Client
{
static public void Main(string[] Args)
{
TcpClient socketForServer;
try
{
socketForServer = new TcpClient("localHost", 10);
}
catch
{
Console.WriteLine(
"Failed to connect to server at {0}:999", "localhost");
return;
}
NetworkStream networkStream = socketForServer.GetStream();
System.IO.StreamReader streamReader =
new System.IO.StreamReader(networkStream);
System.IO.StreamWriter streamWriter =
new System.IO.StreamWriter(networkStream);
Console.WriteLine("*******This is client program who is connected to localhost on port No:10*****");
try
{
string outputString;
// read the data from the host and display it
{
while (true)
{
outputString = streamReader.ReadLine();
Console.WriteLine("Message Recieved by server:" + outputString);
streamWriter.Flush();
}
}
}
catch
{
Console.WriteLine("Exception reading from Server");
}
// tidy up
networkStream.Close();
Console.WriteLine("Press any key to exit from client program");
Console.ReadKey();
}
private static string GetData()
{
//Ack from sql server
return "ack";
}
}
Thank you

simple working multi-threaded server:
static void Process(Socket client) {
Console.WriteLine("Incoming connection from " + client.RemoteEndPoint);
const int maxMessageSize = 1024;
byte[] response;
int received;
while (true) {
// Send message to the client:
Console.Write("Server: ");
client.Send(Encoding.ASCII.GetBytes(Console.ReadLine()));
Console.WriteLine();
// Receive message from the server:
response = new byte[maxMessageSize];
received = client.Receive(response);
if (received == 0) {
Console.WriteLine("Client closed connection!");
return;
}
List<byte> respBytesList = new List<byte>(response);
respBytesList.RemoveRange(received, maxMessageSize - received); // truncate zero end
Console.WriteLine("Client (" + client.RemoteEndPoint + "+: " + Encoding.ASCII.GetString(respBytesList.ToArray()));
}
}
static void Main(string[] args) {
int backlog = -1, port = 2222;
Socket server = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
server.ReceiveTimeout = -1;
// Start listening.
try {
server.Bind(new IPEndPoint(IPAddress.Any, port));
server.Listen(backlog);
}
catch (Exception) {
Console.WriteLine("Listening failed!");
Console.ReadKey();
return;
}
Console.WriteLine("Start listening...");
while(true) {
Socket client = server.Accept();
new System.Threading.Thread(() => {
try { Process(client); } catch (Exception ex) { Console.WriteLine("Client connection processing error: " + ex.Message); }
}).Start();
}
//Console.WriteLine("Press any key for exit...");
//Console.ReadKey();
}
And client:
static void WorkWithServer(Socket server) {
const int maxMessageSize = 1024;
byte[] response;
int received;
while(true) {
try {
// Receive message from the server:
response = new byte[maxMessageSize];
received = server.Receive(response);
if (received == 0) {
Console.WriteLine("Server closed connection.");
return;
}
List<byte> respBytesList = new List<byte>(response);
respBytesList.RemoveRange(received, maxMessageSize - received); // truncate zero end
Console.WriteLine("Server: " + Encoding.ASCII.GetString(respBytesList.ToArray()));
// Send message to the server:
Console.Write("You: ");
server.Send(Encoding.ASCII.GetBytes(Console.ReadLine()));
Console.WriteLine();
}
catch (Exception ex) {
Console.WriteLine("Error: " + ex.Message);
return;
}
}
}
static void Main(string[] args) {
IPEndPoint serverEp = new IPEndPoint(IPAddress.Parse("192.168.1.2"), 2222);
Socket server = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
server.ReceiveTimeout = -1;
// Connect to the server.
try { server.Connect(serverEp); }
catch (Exception) {
Console.WriteLine("Establish connection with server (" + serverEp + ") failed!");
Console.ReadKey();
return;
}
Console.WriteLine("Connection with server (" + serverEp + ") established!");
WorkWithServer(server);
Console.WriteLine("Press any key for exit...");
Console.ReadKey();
}
Edit as you need.

Your code is wrong.
First of all I'll give you some insight of how it's wrong and why it's not working the way you want.
You're creating n number of threads, and making them ALL wait for a connection. What if you exhaust the number of threads? What if any of them exits unexpectedly?
You are also sending the data wrong. By using Console.ReadLine you aren't passing the data through multiple threads and reading the line in each one, instead, the first one that calls Console.ReadLine will be the one that's going to receive it. This means you'll only be sending to only one Socket.
It's not ideal how you're managing this. There are dozens if not hundreds of multithreaded socket server/client available online, and I'd invite you to research a little bit more. But first I'd like you to research more about Thread/Task in C#.

C# socket BeginAccept event stops firing

The code below creates socket server and client
I start the server and if I start one after the other the clients it works fine
If I start three clients immediately, then for one or more clients the BeginAccept event is not fired
The results bellow are after executing the code bellow
Server Started
Server is waiting for a connection...
Client 0.0.0.0:6352 requests connection
Client 0.0.0.0:6353 requests connection
Client 127.0.0.1:6351 requests connection
Client 127.0.0.1:6351 connected
Client 127.0.0.1:6352 connected
Client 127.0.0.1:6353 connected
ServerOnClientConnection Client: 127.0.0.1:6351
Server is waiting for a connection...
ServerOnClientConnection Client: 127.0.0.1:6353
code follows
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Net.Sockets;
using System.Text;
using System.Threading;
using System.Windows.Forms;
namespace Test {
public class TestSockets {
#region server
Socket serverSocket;
bool serverIsAlive;
public ManualResetEvent waitForConnection = new ManualResetEvent(false);
private Encoding encod = Encoding.Unicode;
public void ServerStartInThread() {
byte[] bytes = new Byte[1024];
IPAddress ipAddress = IPAddress.Parse("127.0.0.1");
IPEndPoint localEndPoint = new IPEndPoint(ipAddress, 5500);
Socket socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
serverSocket = socket;
try {
socket.Bind(localEndPoint);
socket.Listen(100);
Thread pollThread = new Thread(delegate () {
serverIsAlive = true; // needs if reopen
SendMessage("Server Started");
while (serverIsAlive) {
try {
SendMessage("Server is waiting for a connection...");
socket.BeginAccept(new AsyncCallback(ServerOnClientConnection), socket);
waitForConnection.Reset();
waitForConnection.WaitOne();
}
catch (Exception ex) {
SendMessage("Server: " + ex.ToString());
}
}
SendMessage("Server Stopped");
socket.Close();
}) {
Name = "SocketServer"
};
pollThread.Start();
}
catch (Exception ex) {
SendMessage("Server: " + ex.ToString());
}
}
public void ServerOnClientConnection(IAsyncResult ar) {
try {
Socket listener = (Socket)ar.AsyncState;
Socket clientSocket = listener.EndAccept(ar);
SendMessage("ServerOnClientConnection Client: " + clientSocket.RemoteEndPoint.ToString());
StateObject state = new StateObject() {
socket = clientSocket
};
clientSocket.BeginReceive(state.buffer, 0, StateObject.BufferSize, 0, new AsyncCallback(ServerReceiveCallback), state);
waitForConnection.Set();
}
catch (Exception ex) {
SendMessage("ServerOnClientConnection: " + ex.ToString());
}
}
public void ServerReceiveCallback(IAsyncResult ar) {
StateObject state = (StateObject)ar.AsyncState;
Socket socket = state.socket;
try {
if (socket == null) return;
if (!socket.Connected) {
return;
}
int bytesRead = socket.EndReceive(ar);
if (bytesRead > 0) {
state.sb.Append(encod.GetString(state.buffer, 0, bytesRead));
socket.BeginReceive(state.buffer, 0, StateObject.BufferSize, 0, new AsyncCallback(ServerReceiveCallback), state);
}
}
catch (Exception ex) {
SendMessage("ServerReceiveCallback: " + ex.ToString());
}
}
#endregion
#region client
private Socket client;
private bool isAlive = false;
private ManualResetEvent connectDone = new ManualResetEvent(false);
public void StartInThread() {
try {
IPAddress ipAddress = IPAddress.Parse("127.0.0.1");
IPEndPoint remoteEP = new IPEndPoint(ipAddress, 5500);
Thread pollThread = new Thread(delegate () {
isAlive = true;
while (isAlive) {
try {
if (client != null && client.Connected) {
continue;
}
client = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
client.BeginConnect(remoteEP, new AsyncCallback(ClientConnectCallback), client);
SendMessage(string.Format("Client {0} requests connection", client.LocalEndPoint.ToString()));
connectDone.Reset();
connectDone.WaitOne(3000, false);
if (client.Connected) {
StateObject state = new StateObject() {
socket = client
};
SendMessage(string.Format("Client {0} connected", client.LocalEndPoint.ToString()));
client.BeginReceive(state.buffer, 0, StateObject.BufferSize, 0, new AsyncCallback(ClientReceiveCallback), state);
}
}
catch (Exception ex) {
SendMessage("ClientStartInThread1: " + ex.ToString());
}
}
SendMessage("Client Disconnected");
}) {
Name = "ClientThread"
};
pollThread.Start();
}
catch (Exception ex) {
SendMessage("ClientStartInThread2: " + ex.ToString());
}
}
private void ClientConnectCallback(IAsyncResult ar) {
try {
Socket socket = (Socket)ar.AsyncState;
socket.EndConnect(ar);
connectDone.Set();
}
catch (Exception ex) {
SendMessage("ClientConnectCallback: " + ex.ToString());
}
}
private void ClientReceiveCallback(IAsyncResult ar) {
StateObject state = (StateObject)ar.AsyncState;
Socket socket = state.socket;
if (socket == null || !socket.Connected) return;
try {
int bytesRead = socket.EndReceive(ar);
if (bytesRead > 0) {
state.sb.Append(encod.GetString(state.buffer, 0, bytesRead));
socket.BeginReceive(state.buffer, 0, StateObject.BufferSize, 0, new AsyncCallback(ClientReceiveCallback), state);
}
else {
socket.Close();
}
}
catch (Exception ex) {
SendMessage("ClientReceiveCallback: " + ex.ToString());
socket.Close();
}
}
#endregion
private void SendMessage(string v) {
System.Diagnostics.Debug.WriteLine(v);
}
public static void Start() {
TestSockets server = new TestSockets();
server.ServerStartInThread();
TestSockets c1 = new TestSockets();
c1.StartInThread();
TestSockets c2 = new TestSockets();
c2.StartInThread();
TestSockets c3 = new TestSockets();
c3.StartInThread();
}
}
public class StateObject {
public Socket socket = null;
public const int BufferSize = 1024;
public byte[] buffer = new byte[BufferSize];
public StringBuilder sb = new StringBuilder();
}
}

You have a race condition in your code that results in the waitForConnection event handle being set twice, with the second call to Set() having no effect, before the main server thread has a chance to proceed past the BeginAccept() and reset the handle. This causes it to miss the second set.
One way to fix it would be to switch to a semaphore object. For example:
#region server
Socket serverSocket;
bool serverIsAlive;
SemaphoreSlim waitForConnection = new SemaphoreSlim(0);
private Encoding encod = Encoding.Unicode;
public void ServerStartInThread()
{
byte[] bytes = new Byte[1024];
IPAddress ipAddress = IPAddress.Parse("127.0.0.1");
IPEndPoint localEndPoint = new IPEndPoint(ipAddress, 5500);
Socket socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
serverSocket = socket;
try
{
socket.Bind(localEndPoint);
socket.Listen(100);
Thread pollThread = new Thread(delegate () {
serverIsAlive = true; // needs if reopen
SendMessage("Server Started");
while (serverIsAlive)
{
try
{
SendMessage("Server is waiting for a connection...");
socket.BeginAccept(new AsyncCallback(ServerOnClientConnection), socket);
waitForConnection.Wait();
}
catch (Exception ex)
{
SendMessage("Server: " + ex.ToString());
}
}
SendMessage("Server Stopped");
socket.Close();
})
{
Name = "SocketServer"
};
pollThread.Start();
}
catch (Exception ex)
{
SendMessage("Server: " + ex.ToString());
}
}
public void ServerOnClientConnection(IAsyncResult ar)
{
try
{
Socket listener = (Socket)ar.AsyncState;
Socket clientSocket = listener.EndAccept(ar);
SendMessage("ServerOnClientConnection Client: " + clientSocket.RemoteEndPoint.ToString());
StateObject state = new StateObject()
{
socket = clientSocket
};
clientSocket.BeginReceive(state.buffer, 0, StateObject.BufferSize, 0, new AsyncCallback(ServerReceiveCallback), state);
waitForConnection.Release();
}
catch (Exception ex)
{
SendMessage("ServerOnClientConnection: " + ex.ToString());
}
}
This will allow the ServerOnClientConnection() method to increment the semaphore count, so that the main server thread can continue to loop until all of the accepted connections have been observed.
However, frankly, the MSDN examples that use these event handles (which is what I'm assuming your code is based on, either directly or indirectly) are IMHO simply broken. They introduce thread synchronization complexities where none is actually needed, unnecessarily complicating the code and making it harder to get the code to work correctly.
A more idiomatic approach would be to not have the extra thread at all, call BeginAccept() once in the ServerStartInThread() method (which you'd probably rename to just ServerStart()) and call BeginAccept() in the ServerOnClientConnection() method after handling the currently accepted client. I.e. just like you handle the BeginReceive() now.
That said, IMHO even the idiomatic approach is outdated. It worked very well when the API was first designed, but .NET has come a long way since then and has much better mechanisms for dealing with asynchronous operations like this. I posted in this answer an example of a simple chat server that shows how you can use async/await to implement this sort of thing in a much simpler, easier-to-read way. You may want to look at that for ideas on how to apply the same techniques to your own code.

C# server and client not working

I have been making a C# server and client for a game. I have used many resources to try to create something successful. So far, the client can send stuff to the server and the server can receive them, but I want to be able to send stuff to the client. Also, I don't know what happened, but my server code suddenly stopped printing to console or something. I am new at this and any help is needed. I think I programmed both client and server to be able to send and receive, but something isn't right...
Note: I am using a cmd compiler running an old version of the .NET (but the code still compiles), any help on getting visual studio working to build/compile the code would also be nice :)
Client-side:
using System;
using System.Net;
using System.Net.Sockets;
using System.Text;
using System.Threading;
class Program
{
static Boolean done = false;
static void Main(string[] args)
{
Boolean exception_thrown = false;
Socket sending_socket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram,
ProtocolType.Udp);
IPAddress send_to_address = IPAddress.Parse("ip-goes-here");
IPEndPoint sending_end_point = new IPEndPoint(send_to_address, 27020);
Console.WriteLine("Enter text to broadcast via UDP.");
Console.WriteLine("Enter a blank line to exit the program.");
Thread listenerT = new Thread(new ThreadStart(Program.listener));
listenerT.Start();
while (!done)
{
Console.WriteLine("Enter text to send, blank line to quit");
string text_to_send = Console.ReadLine();
if (text_to_send.Length == 0)
{
done = true;
listenerT.Abort();
}
else
{
byte[] send_buffer = Encoding.ASCII.GetBytes(text_to_send);
Console.WriteLine("sending to address: {0} port: {1}",
sending_end_point.Address,
sending_end_point.Port);
try
{
sending_socket.SendTo(send_buffer, sending_end_point);
}
catch (Exception send_exception)
{
exception_thrown = true;
Console.WriteLine(" Exception {0}", send_exception.Message);
}
if (exception_thrown == false)
{
Console.WriteLine("Message has been sent to the broadcast address");
}
else
{
exception_thrown = false;
Console.WriteLine("The exception indicates the message was not sent.");
}
}
}
}
static void listener()
{
int listenPort = 27020;
UdpClient listener = new UdpClient(listenPort);
IPEndPoint groupEP = new IPEndPoint(IPAddress.Any, listenPort);
string received_data;
byte[] receive_byte_array;
try
{
while (!done)
{
Console.WriteLine("Waiting for broadcast");
receive_byte_array = listener.Receive(ref groupEP);
Console.WriteLine("Received a broadcast from {0}", groupEP.ToString());
received_data = Encoding.ASCII.GetString(receive_byte_array, 0, receive_byte_array.Length);
Console.WriteLine("data follows \n{0}\n\n", received_data);
}
}
catch (Exception e)
{
Console.WriteLine(e.ToString());
}
}
}
Server side:
using System;
using System.Net;
using System.Net.Sockets;
using System.Text;
using System.Threading;
public class UDPListener
{
private const int listenPort = 27020;
//static Boolean done = false;
static IPEndPoint groupEP = new IPEndPoint(IPAddress.Any, listenPort);
static UdpClient udpServer = new UdpClient(27020);
static IPEndPoint remoteEP = new IPEndPoint(IPAddress.Any, 27020);
static byte[] data = udpServer.Receive(ref remoteEP); // listen on port 11000
static IPAddress send_to_address = IPAddress.Parse("10.240.0.1");
static IPEndPoint sending_end_point = new IPEndPoint(send_to_address, 27020);
public static void Main()
{
Console.WriteLine("Begin listening sequence");
while (true)
{
data = udpServer.Receive(ref groupEP);
Console.WriteLine("Received a broadcast from {0}", groupEP.ToString());
send_to_address = IPAddress.Parse(groupEP.ToString());
Thread listenerT = new Thread(new ThreadStart(UDPListener.sender));
listenerT.Start();
String received_data = Encoding.ASCII.GetString(data, 0, data.Length);
Console.WriteLine(received_data);
}
}
static void sender()
{
while (true)
{
Console.WriteLine("Enter text to send, blank line to quit");
string text_to_send = Console.ReadLine();
if (text_to_send.Length == 0)
{
//done = true;
}
else
{
byte[] send_buffer = Encoding.ASCII.GetBytes(text_to_send);
Console.WriteLine("sending to address: {0} port: {1}",
sending_end_point.Address,
sending_end_point.Port);
udpServer.Send(send_buffer, 0, remoteEP); // reply back
}
}
}
}

Nevermind, a friend of mine figured it out. You can find the final code in a github repo called something like flaming leaf server

Issue with passing a variable C#

I am working on a project where I am going to create a TCP/IP Chat application and I have some problems with passing variables between the classes. The variable data does not get passed on from the handleClient to the main class where data along with clientSocket is saved to a Hashtable. The Hashtable is later going to be used for broadcasting the message to all clients. The error i get is as follows: "Error: The name 'data' does not exist in the current context"
Serverside code:
using System;
using System.IO;
using System.Data;
using System.Net;
using System.Net.Sockets;
using System.Text;
using System.Threading;
using System.Collections;
namespace Chat_server
{
public class Program
{
//Creates a list with all clients
public static Hashtable clientList = new Hashtable();
public void Main(string[] args)
{
TcpListener serverSocket = null;
// Set the TcpListener on port 13000.
Int32 port = 13000;
IPAddress localAddr = IPAddress.Parse("127.0.0.1");
// TcpListener server = new TcpListener(port);
serverSocket = new TcpListener(localAddr, port);
// Start listening for client requests.
serverSocket.Start();
int counter = 0;
while (true)
{
counter += 1;
Console.WriteLine("Waiting for a connection... ");
TcpClient clientSocket = serverSocket.AcceptTcpClient();
clientList.Add(data, clientSocket);
Console.WriteLine(" >> " + "Client No:" + Convert.ToString(counter) + " started!");
handleClient hclient = new handleClient();
hclient.startClient(clientSocket);
}
}
}
}
//Class to handle each connection separatly
public class handleClient
{
TcpClient clientSocket;
Hashtable clientList;
public void startClient(TcpClient inClient)
{
this.clientSocket = inClient;
Thread clientThread = new Thread(new ThreadStart(doChat));
clientThread.Start();
}
public void doChat()
{
Byte[] bytes = new Byte[10025];
String data = null;
data = null;
while ((true))
{
try
{
foreach (DictionaryEntry Item in clientList)
{
data = null;
// Get a stream object for reading and writing
NetworkStream stream = clientSocket.GetStream();
int i;
// Loop to receive all the data sent by the client.
while ((i = stream.Read(bytes, 0, bytes.Length)) != 0)
{
// Translate data bytes to a ASCII string.
data = System.Text.Encoding.ASCII.GetString(bytes, 0, i);
Console.WriteLine("Received: {0}", data);
byte[] msg = System.Text.Encoding.ASCII.GetBytes(data);
// Send back a response.
stream.Write(msg, 0, msg.Length);
stream.Flush();
Console.WriteLine("Sent: {0}", data);
}
// Shutdown and end connection
clientSocket.Close();
}
}
catch (SocketException e)
{
Console.WriteLine("SocketException: {0}", e);
}
finally
{
}
}
}
}

data isn't defined in that function or in the class at:
clientList.Add(data, clientSocket);

Server remains hang when sending

I'm writting a client(Android) - server(c#) application. I get the code from here:
How to make client on Android listen to server on C#?
Everythings is working fine, when i just send message from the client to server, and from server to client (closing the socket on server side). Now, what i want is : send message to server, receive message from server, then send again a message to server. The server hangs at sending the message. If i close the socket on server side after sending, it gives a dispose error, and i can's send the data from the server.
My server code is:
/*************************************SERVER*****************************/
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net;
using System.Net.Sockets;
namespace SERVER2
{
class Program
{
public static void Main()
{
try
{
IPAddress ipAd = IPAddress.Parse("192.168.2.102");
TcpListener myList = new TcpListener(ipAd, 18001);
myList.Start();
Console.WriteLine("The server is running at port 18001...");
Console.WriteLine("The local End point is :" +
myList.LocalEndpoint);
Console.WriteLine("Waiting for a connection.....");
m:
Socket s = myList.AcceptSocket();
Console.WriteLine("Connection accepted from " + s.RemoteEndPoint);
byte[] b = new byte[100];
int k = s.Receive(b);
char cc = ' ';
string test = null;
Console.WriteLine("Recieved1...");
for (int i = 0; i < k - 1; i++)
{
cc = Convert.ToChar(b[i]);
test += cc.ToString();
}
Console.WriteLine("Received characters1: "+test);
ASCIIEncoding asen = new ASCIIEncoding();
s.Send(asen.GetBytes("The string was recieved by the server."));
Console.WriteLine("\nSent Acknowledgement");
//s.Close(); <-if i enable this, i get a dispose error
k = s.Receive(b);//i get dispose error here
cc = ' ';
test = null;
Console.WriteLine("Recieved2...");
for (int i = 0; i < k - 1; i++)
{
cc = Convert.ToChar(b[i]);
test += cc.ToString();
}
Console.WriteLine("Received characters2: " + test);
/* clean up */
goto m;
s.Close();
myList.Stop();
}
catch (Exception e)
{
Console.WriteLine("Error..... " + e.Message);
}
Console.ReadLine();
}
}
}
My client code is:
/******************************CLIENT*****************************************/
Socket socket = null;
try
{
Toast.makeText(context,"IP: "+ip+" port: "+port,10000).show();
InetAddress serverAddr = InetAddress.getByName(ip);
socket = new Socket(serverAddr, port);
}
catch (UnknownHostException e1)
{
Toast.makeText(context,"UnknownHostException ",10000).show();
}
catch (IOException e1)
{
Toast.makeText(context,"IOException ",10000).show();
}
String message = "1";
PrintWriter out = null;
BufferedReader in = null;
try {
Log.d("TCP", "C: Sending: '" + message + "'");
/*write*/
out = new PrintWriter( new BufferedWriter( new OutputStreamWriter(socket.getOutputStream())),true);
out.println(message);
out.flush();
/*read*/
in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
String text = "";
String finalText = "";
while ((text = in.readLine()) != null)
{
finalText += text;
}
Toast.makeText(context, "FinalText: "+finalText, 10000).show();
Log.d("TCP", "C: Sent.");
Log.d("TCP", "C: Done.");
in.close();
/*write*/
out = new PrintWriter( new BufferedWriter( new OutputStreamWriter(socket.getOutputStream())),true);
out.println(message);
out.flush();
} catch(Exception e) {
Log.e("TCP", "S: Error", e);
} finally {
try {
socket.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
Thanks advanced !!!

The reason you get the dispose error is because the s.close() closes the socket, and then your next s.Receive() is trying to read from a closed socket.
Also the hang you are seeing might be caused by in.close(); in your java code. It could be closing the underlying socket. Try commenting it out and see if that fixes your hanging problem.
Not an expert in C#, but I've done my share of socket programming.
Basically what you want is 1 + n threads.
One thread that just accepts connections.
For each socket that is returned by Socket s = myList.AcceptSocket(); you want a thread for sending/receiving data and processing the messages from the socket. You could also use two threads (one that sends, one that receives (this is the asynchronous case)).

You should use the stream of the tcp client.. an example can be found here: http://msdn.microsoft.com/de-de/library/system.net.sockets.tcplistener.aspx
And don't use goto, please.
You will never reach the end lines after goto m;
Surround the code with a while loop which checks if an timeout is occured or any other checks.
The reason why the server hangs is that he waits for 100 bytes to receive.

The problem was that when the client received the message from the server , in the while part entered into an infinite loop. I modify my app like this:
My client part:
try
{
Toast.makeText(context,"IP: "+ip+" port: "+port,10000).show();
InetAddress serverAddr = InetAddress.getByName(ip);
socket = new Socket(serverAddr, port);
}
catch (UnknownHostException e1)
{
Toast.makeText(context,"UnknownHostException ",10000).show();
}
catch (IOException e1)
{
Toast.makeText(context,"IOException ",10000).show();
}
String message = "HELLO FROM CLIENT";
PrintWriter out = null;
BufferedReader in = null;
try {
Log.d("TCP", "C: Sending: '" + message + "'");
/*write*/
OutputStream ostr=socket.getOutputStream();
OutputStreamWriter outputstr=new OutputStreamWriter(ostr);
BufferedWriter buffw=new BufferedWriter(outputstr);
out = new PrintWriter(buffw ,true);
out.println("HELLO 1 FROM CLIENT");
/*read - i modify to this*/
InputStreamReader reader=new InputStreamReader(socket.getInputStream());
char[] bytesreceived=new char[50];
reader.read(bytesreceived , 0, 50);
String text="";
for (int i=0;i<bytesreceived.length;i++)
{
text+=bytesreceived[i];
}
Toast.makeText(context, "Received1: "+text.trim(), 10000).show();
Log.d("IdealLog","Received1: "+text.trim());
/*write*/
out = new PrintWriter( new BufferedWriter( new OutputStreamWriter(socket.getOutputStream())),true);
out.println("HELLO 2 FROM CLIENT");
/*read*/
reader=new InputStreamReader(socket.getInputStream());
bytesreceived=new char[50];
reader.read(bytesreceived , 0, 50);
text="";
for (int i=0;i<bytesreceived.length;i++)
{
text+=bytesreceived[i];
}
Toast.makeText(context, "Received2: "+text.trim(), 10000).show();
Log.d("IdealLog","Received2: "+text.trim());
} catch(Exception e) {
Log.e("TCP", "S: Error", e);
} finally {
try {
socket.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
My server side code:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net;
using System.Net.Sockets;
using System.Threading;
namespace SocketServer
{
class Program
{
static void Main(string[] args)
{
IPEndPoint ip = new IPEndPoint(IPAddress.Any, 18001);
Socket socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
socket.Bind(ip);
socket.Listen(10);
Console.WriteLine("Waiting for a client...");
Socket client = socket.Accept();
IPEndPoint clientep = (IPEndPoint)client.RemoteEndPoint;
Console.WriteLine("Connected with {0} at port {1}", clientep.Address, clientep.Port);
string welcome = "HELLO 1 FROM SERVER";
byte[] data = new byte[200];
int receiveddata=client.Receive(data);
Console.WriteLine("Received data from CLIENT1: {0}", System.Text.ASCIIEncoding.ASCII.GetString(data).Trim());
ASCIIEncoding asen = new ASCIIEncoding();
byte[] data2 = new byte[200];
data2 = asen.GetBytes(welcome);
int sentdata=client.Send(data2, data2.Length, SocketFlags.None);
Console.WriteLine("Sent data from SERVER: {0}", welcome);
byte[] data3 = new byte[200];
Console.WriteLine("Receiving data from CLIENT : {0}", "...");
client.Receive(data3);
Console.WriteLine("Received data from CLIENT2: {0}", System.Text.ASCIIEncoding.ASCII.GetString(data3).Trim());
byte[] data4 = new byte[200];
data4 = asen.GetBytes("HELLO 2 FROM SERVER");
sentdata = client.Send(data4, data4.Length, SocketFlags.None);
client.Close();
socket.Close();
Console.WriteLine("Disconnected from {0}", clientep.Address);
Console.ReadLine();
}
}
}
Now, everything is working fine, without hang. The only problem is, that i don't know if this will work for receiving , sending files.