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C# UDP Socket.ReceiveFrom() breaks loop without exeption

I'm trying to make a game using sockets and UDP, i made a server class where when i call the start method i run a task with a loop to receive packets and process them, i used Socket.ReceiveFrom(packet, ref sender); inside a try catch block with everything inside a while loop, first i forgot to add Socket.Bind(new IPEndPoint(IPAddress.Parse("127.0.0.1"), 25000)); so i got a loop of bind exeptions which is normal but now that i added this line my program is freaking out see the code bellow
public class UDPServer
{
public UDPServer()
{
Socket = new Socket(AddressFamily.InterNetwork ,SocketType.Dgram,ProtocolType.Udp);
Socket.Bind(new IPEndPoint(IPAddress.Parse("127.0.0.1"), 25000));
}
public void Start()
{
IsBound = true;
try
{
Task.Run(NetworkLoop);
}
catch (Exception e)
{
throw e;
}
}
private void NetworkLoop()
{
EndPoint sender = new IPEndPoint(IPAddress.Any, 0);
byte[] packet = new byte[1];
int dataSize = 0;
while (IsBound)
{
try
{
dataSize = Socket.ReceiveFrom(packet, ref sender);
Console.WriteLine(sender.ToString() + " with " + packet.Length + " of " + dataSize);
}
catch (Exception e)
{
Console.WriteLine("Reading exeption : " + e.Message);
}
}
}
}
I debugged this and it seems that now when going step by step to the line
dataSize = Socket.ReceiveFrom(packet, ref sender); it just both exit the try catch block without any exeption catched AND breaks the while loop...
Is this normal behaviour ??

Your UDPServer.Start() method is not blocking, because Task.Run will run asynchronously.
Task.Run(NetworkLoop); // This is non-blocking
Your UDP server will work by either:
Task.Run(NetworkLoop).Wait(); // This is blocking
or
new UDPServer().Start();
Console.WriteLine("Press <enter> key to stop UDP server...");
Console.ReadLine(); // This block until user hit <enter> key

Socket: Disposing connection twice?

I'm trying to work this one out but it really is a head scratcher, a socket is meant to make two connections to the server, the second one being the legitamate connection. I have this method that I attach to my callback for beginReceive method although its calling Dispose twice?
Usually it only calls it once as the client makes 2 connections to the server, the second one being legitamate but it seems this method wants to call Dispose twice, which makes me think theres something wrong, could somebody verify if there is anything wrong with this?
private void OnIncomingData(IAsyncResult asyncResult)
{
int bytesReceived;
try
{
bytesReceived = _socket.EndReceive(asyncResult);
}
catch
{
Dispose();
return;
}
if (bytesReceived == 0)
{
Dispose();
return;
}
try
{
var packet = new byte[bytesReceived];
Array.Copy(_buffer, packet, bytesReceived);
var received = Encoding.UTF8.GetString(packet);
var packetData = JObject.Parse(received).ToFlatDictionary();
var incomingPacket = new IncomingPacket(packetData);
CoreUtilities.LogToConsole("Received packet: " + incomingPacket.Id + "\n\n" + received);
if (_session.PacketProvider.PacketEvents.TryGetValue(incomingPacket.Id, out var packetEvent))
{
packetEvent.Invoke(_session, incomingPacket);
CoreUtilities.LogToConsole("Finished executing packet " + packetEvent.GetType().Name + " for " + incomingPacket.Id);
}
else
{
CoreUtilities.LogToConsole("Failed to execute unknown incoming packet: " + incomingPacket.Id);
}
}
catch
{
Dispose();
}
finally
{
try
{
_socket.BeginReceive(_buffer, 0, _buffer.Length, SocketFlags.None, OnIncomingData, _socket);
}
catch
{
Dispose();
}
}
}

TcpClient hangs

I am working on a simple Client to send data to a server at my office. I tested the code locally on my computer using a server called TCPServer, I connect, send data, receive reply, disconnect, send again, rinse and repeat, it all works perfectly, but when I connect to office and do the same thing it connects fine, I can connect/disconnect forever, but when I send data it just hangs. Nothing is received in the log at the office. I can't send a single byte there.
Seems like a firewall issue doesn't it.
But I can run an older program I wrote years ago in Delphi (pascal), and it connects and sends the same data over without issue, same port, everything, so the problem is not a firewall issue. Thoughts on this? Here is the basic code layout.
Connect Button
Disconnect Button
Send Button
At the top of the class I declare the TcpClient Variable
public TcpClient m_client = new TcpClient();
In the _Click for Connect Button and Disconnect Button I have code to connect to server and set some indicators etc
private void ConnectButton_Click(object sender, EventArgs e)
{
string address = FixIP(IPAddressMaskedTextBox.Text);
int Port = Convert.ToInt32(PortNumberMaskedTextBox.Text);
Control control = (Control)sender;
String name = control.Name;
try
{
switch (name)
{
case ("ConnectButton"):
//Connect to server
connect(address, Port);
if (m_client.Connected)
{
SingleConnectionRichTextBox.Clear();
ConnectedLightButton.BackColor = Color.Lime;
SingleConnectionRichTextBox.Text += "Connected at IP " + address + " and Port " + Port.ToString() + "\r\n";
}
break;
case ("DisconnectButton"):
if (m_client.Connected)
{
SingleConnectionRichTextBox.Text += "Connection Terminated\r\n";
ConnectedLightButton.BackColor = Color.Red;
m_client.Client.Disconnect(false);
m_client = new TcpClient();
}
break;
}
}
catch (Exception err)
{
MessageBox.Show(err.ToString());
}
}
public void connect(string address, int port)
{
try
{
if (!m_client.Connected)
{
ConnectedLightButton.BackColor = Color.Yellow;
SingleConnectionRichTextBox.Text += "Attempting to Connect...\r\n";
m_client.Connect(address, port);
}
else
{
SingleConnectionRichTextBox.Text += "Connection Failed...\r\n";
ConnectedLightButton.BackColor = Color.Red;
throw new Exception("Connect: Already connected\r\n");
}
}
catch (Exception err)
{
MessageBox.Show(err.ToString());
}
}
The Send button has it's own event, mostly because when connecting to office it can take a minute for sockets to be created etc.
private void SendButton_Click(object sender, EventArgs e)
{
try
{
if (m_client.Connected)
{
string completeString = "";
for (int cnt = 0; cnt < SingleSendRichTextBox.Lines.Count() - 1; cnt++)
{
string aLine = Regex.Replace(SingleSendRichTextBox.Lines[cnt], #"\e\[(\d+;)*(\d+)?[ABCDHJKfmsu]", "");
if (cnt == 0)
{
//First line gets Start Block, plus a CR on end
aLine = (char)0x0B + aLine + (char)0x0D;
}
else if (cnt == (SingleSendRichTextBox.Lines.Count() -1))
{
//Last line gets CR + End Block + CR on end
aLine += (char)0x0D + (char)0x1C + (char)0x0D;
}
else
{
//All middle lines get CR on end
aLine += (char)0x0D;
}
//MessageBox.Show("Sending line# " + cnt.ToString() + " = " + aLine);
completeString += aLine;
}
Byte[] data = Encoding.ASCII.GetBytes(completeString);
WriteBytes(data);
ReadAllBytes();
}
else
{
MessageBox.Show("Nothing is connected currently...");
}
}
catch (Exception err)
{
MessageBox.Show(err.ToString());
}
}
public void WriteBytes(Byte[] data)
{
try
{
if ((m_client.Connected)&&(data.Count() > 0))
{
// Get access to network stream
NetworkStream stm = m_client.GetStream();
stm.Write(data, 0, data.Length);
stm.Flush();
//MessageBox.Show("Data Sent, length = " + data.Length.ToString());
}
else
{
MessageBox.Show("Either we are not connected, or there is no data to send!!");
}
}
catch (Exception err)
{
MessageBox.Show(err.ToString());
}
}
public void ReadAllBytes()
{
try
{
// Buffer to store the response bytes.
Byte[] readdata = new Byte[256];
// String to store the response ASCII representation.
String responseData = String.Empty;
NetworkStream stm = m_client.GetStream();
// Read the first batch of the TcpServer response bytes.
Int32 bytes = stm.Read(readdata, 0, readdata.Length);
responseData = Encoding.ASCII.GetString(readdata, 0, bytes);
SingleReplyRichTextBox.Text += responseData + "\r\n";
}
catch (Exception err)
{
MessageBox.Show(err.ToString());
}
}
Does anything in here raise a red flag that is obvious? I tried Stream VS NetworkStream. I tried turning off the Reply listener. I took this code and combined it all into one function, and moved the TcpClient creation over to a different Class as static so I could create it in each function, but while all of these worked fine locally, nothing works connecting to office. It won't send a single byte. I set m_client as static at the top too, works fine locally, not to office.
Is GetStream failing maybe? or its sending the data on a different socket?

use a Task and cancellation token to cancel the task. Don't init a "new" TCPclient. In the background the TCPclient will be not closed (socket-timeout of .net)
Use try catches to see the exception and add the log to the conversation to make it more clear pls

Send a flag from server to clients using c# mouse events

I am using sockets in c# in order to send data from server to client machine. In fact I have created a capturer which capature kinect stream from 3 different machine. I want to generate a server and client communication in order to send signal from server to the rest devices in order to begin and stop the recording process. I want with left click to send a message to begin recording and with right click to stop recording. My code is the following:
public Form1()
{
InitializeComponent();
this.MouseClick += mouseClick1;
Thread thread = new Thread(() => StartServer(message));
thread.Start(); // server is begining
}
private void mouseClick1(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
message = "start";
try
{
obj = new Capturer(dirPath + name + "_" + surname, 20);
}
catch (Exception e1)
{
Console.WriteLine("The process failed: {0}", e1.ToString());
}
if (clientSockets.Count > 0)
{
Thread.Sleep(10);
foreach (Socket socket1 in clientSockets)
socket1.Send(Encoding.ASCII.GetBytes(message)); //send everything to all clients as bytes
}
else
{
serverSocket.BeginAccept(new AsyncCallback(acceptCallback), null); //to receive another client
}
}
else if (e.Button == MouseButtons.Right)
{
message = "stop";
obj.flag2 = true;
if (clientSockets.Count > 0)
{
Thread.Sleep(10);
foreach (Socket socket1 in clientSockets)
socket1.Send(Encoding.ASCII.GetBytes(message)); //send everything to all clients as bytes
}
else
{
serverSocket.BeginAccept(new AsyncCallback(acceptCallback), null); //to receive another client
}
}
}
public void StartServer(String message) {
serverSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
serverSocket.Bind(new IPEndPoint(IPAddress.Any, PORT_NO));
serverSocket.Listen(4); //the maximum pending client, define as you wish
serverSocket.BeginAccept(new AsyncCallback(acceptCallback), null);
string result = "";
do
{
result ="asdf";
} while (result.ToLower().Trim() != "exit");
}
private const int BUFFER_SIZE = 4096;
private static byte[] buffer = new byte[BUFFER_SIZE]; //buffer size is limited to BUFFER_SIZE per message
private static List<Socket> clientSockets = new List<Socket>(); //may be needed by you
private static void acceptCallback(IAsyncResult result)
{ //if the buffer is old, then there might already be something there...
Socket socket = null;
try
{
socket = serverSocket.EndAccept(result); // The objectDisposedException will come here... thus, it is to be expected!
//Do something as you see it needs on client acceptance
clientSockets.Add(socket);
socket.BeginReceive(buffer, 0, buffer.Length, SocketFlags.None, new AsyncCallback(receiveCallback), socket);
string msg = "start";
//socket.Send(Encoding.ASCII.GetBytes(msg));
if (clientSockets.Count > 0)
{
Thread.Sleep(10);
foreach (Socket socket1 in clientSockets)
socket1.Send(Encoding.ASCII.GetBytes(msg)); //send everything to all clients as bytes
}
else
{
serverSocket.BeginAccept(new AsyncCallback(acceptCallback), null); //to receive another client
}
}
catch (Exception e)
{ // this exception will happen when "this" is be disposed...
//Do something here
Console.WriteLine(e.ToString());
}
}
const int MAX_RECEIVE_ATTEMPT = 10;
static int receiveAttempt = 0; //this is not fool proof, obviously, since actually you must have multiple of this for multiple clients, but for the sake of simplicity I put this
private static void receiveCallback(IAsyncResult result)
{
Socket socket = null;
try
{
socket = (Socket)result.AsyncState; //this is to get the sender
if (socket.Connected)
{ //simple checking
int received = socket.EndReceive(result);
if (received > 0)
{
byte[] data = new byte[received]; //the data is in the byte[] format, not string!
Buffer.BlockCopy(buffer, 0, data, 0, data.Length); //There are several way to do this according to http://stackoverflow.com/questions/5099604/any-faster-way-of-copying-arrays-in-c in general, System.Buffer.memcpyimpl is the fastest
//DO SOMETHING ON THE DATA int byte[]!! Yihaa!!
Console.WriteLine(Encoding.UTF8.GetString(data)); //Here I just print it, but you need to do something else
//Message retrieval part
//Suppose you only want to declare that you receive data from a client to that client
string msg = "I receive your message on: " + DateTime.Now;
socket.Send(Encoding.ASCII.GetBytes(msg)); //Note that you actually send data in byte[]
Console.WriteLine("I sent this message to the client: " + msg);
receiveAttempt = 0; //reset receive attempt
//socket.BeginReceive(buffer, 0, buffer.Length, SocketFlags.None, new AsyncCallback(receiveCallback), socket); //repeat beginReceive
}
else if (receiveAttempt < MAX_RECEIVE_ATTEMPT)
{ //fail but not exceeding max attempt, repeats
++receiveAttempt; //increase receive attempt;
socket.BeginReceive(buffer, 0, buffer.Length, SocketFlags.None, new AsyncCallback(receiveCallback), socket); //repeat beginReceive
}
else
{ //completely fails!
Console.WriteLine("receiveCallback fails!"); //don't repeat beginReceive
receiveAttempt = 0; //reset this for the next connection
}
}
}
catch (Exception e)
{ // this exception will happen when "this" is be disposed...
Console.WriteLine("receiveCallback fails with exception! " + e.ToString());
}
}
How can I parse the flag into the server, in order to send that value in the clients? Is it possible to change here the static type of server functions? As it is now the code begin the server which send just the string "start" to the clients. How can I send the string message of a bool flag? My issue lies in the static type of my callback functions. Is it possible to add as an argument the message for example in the AsyncCallBack:
serverSocket.BeginAccept(new AsyncCallback(acceptCallback), null);

Firstly, about the MouseClick event. Since you are having exclusive qualification for the event (that is, one left click and another right click), you could combine them both into a single event
public Form1()
{
InitializeComponent();
this.MouseClick += mouseClick1; //one event is enough
Thread thread = new Thread(() => StartServer(message));
thread.Start(); // server is begining
}
private void mouseClick1(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
try
{
obj = new Capturer(dirPath + name + "_" + surname, 20); //captures the kinect streams
}
catch (Exception e1)
{
Console.WriteLine("The process failed: {0}", e1.ToString());
}
}
else if (e.Button == MouseButtons.Right)
{
obj.flag2 = true; // flag that handle the recording, true value stops the recording, possible I want that value to be send to the client in order the same thing happen.
}
}
And it is going to be ok.
Next, answering your questions:
Q: How can I parse the flag into the server, in order to send that value
in the clients?
A: in your mouseClick1 event, simply use sync send which you do in your accept callback, change the msg with something else (say byte[] val = new byte[] { 1 };)
foreach (Socket socket1 in clientSockets) //Do this in your `if (e.Button == Mouse.Left and Mouse.Right) blocks
socket1.Send(Encoding.ASCII.GetBytes(msg));
Q: Is it possible to change here the static type of server functions?
A: Yes, definitely! it is windows form, you do not need to use static
type at all! Unlike the Console App in your previous question. I would
even suggest you to make nothing static whenever possible
Q: As it is now the code begin the server which send just the string
"start" to the clients. How can I send the string message of a bool
flag?
A: since you use socket, you cannot really send bool flag so to
speak. You will send byte[]. But you can always check in your
client implementation. If the byte[] is of certain value, simply
change it to bool. For instance, consider of sending just 1 or 0
from your server. Then in your client endReceiveCallback, you could
simply check the data coming and see if it is 1 then it is true,
and if it is 0 then it is false
Q: My issue lies in the static type of my callback functions. Is it
possible to add as an argument the message for example in the
AsyncCallBack
A: this is winform, you could get rid of all static var! And yes,
just pass it as replacement of the null in your Begin callback.
Then you pass the object too.
//Change null with something else
serverSocket.BeginAccept(new AsyncCallback(acceptCallback), myobj);
Then in your acceptCallback, take your object by using the IAsyncResult.AsyncState

Chat service application

I am making a chat service for a game,
I am using a TCP listener an client for the account information, some sort of login service. I'm wondering if i can keep the socked the client connected to the server with, to check if he is still online, and keep sending him messages if he has new messages.
I already tried making a list of sockets for the login queue, but it disconnected the previous socket to to server as soon as i accepted a new socket.
byte[] usernameByte = new byte[100];
int usernameRecieved = s.Receive(usernameByte);
//guiController.setText(System.DateTime.Now + " Recieved Login...");
byte[] passByte = new byte[100];
int passRecieved = s.Receive(passByte);
//guiController.setText(System.DateTime.Now + " Recieved Password...");
string username = "";
string password = "";
for (int i = 0; i < usernameRecieved; i++)
username += (Convert.ToChar(usernameByte[i]));
for (int i = 0; i < passRecieved; i++)
password += (Convert.ToChar(passByte[i]));
if (DomainController.getInstance().checkAccount(username, password))
{
ASCIIEncoding asen = new ASCIIEncoding();
s.Send(asen.GetBytes("true"));
s.Send(asen.GetBytes("U are succesfully logged in, press enter to continue"));
guiController.setText(serverName,System.DateTime.Now+"");
guiController.setText(serverName, "Sent Acknowledgement - Logged in");
}
else
{
ASCIIEncoding asen = new ASCIIEncoding();
s.Send(asen.GetBytes("false"));
s.Send(asen.GetBytes("U are NOT logged in, press enter to continue"));
guiController.setText(serverName, System.DateTime.Now + "");
guiController.setText(serverName, "\nSent Acknowledgement - Not logged in");
}
This is the code i currently use to check the account information the user send me. Right after i send this the user dropd the connection and i move on to the next one.
I have tried making 1 list of seperate sockets and processing them one by one, but that failed because the previous socket's connection dropped, even tho it were 2 different machines that tried to connect.
Does anyone have a sollution / a way to save sockets, that I can use to make the program keep all the connections alive? so i can send a message from user 1 to user 2, and just use the socket they connected with? or do i need to add an id every time they make a connection?
EDIT
The client Code: (this is just a test client)
while (true)
{
TcpClient tcpclnt = new TcpClient();
Console.WriteLine("Connecting.....");
tcpclnt.Connect("xx.xxx.xxx.xx", 26862);
// use the ipaddress as in the server program
while(!(checkResponse(tcpclnt.GetStream())))
{
Thread.Sleep(1000);
}
Console.WriteLine("Connected");
Console.Write("Enter the string to be transmitted : ");
String str = Console.ReadLine();
if (str == "")
{
str = " ";
}
Stream stm = tcpclnt.GetStream();
ASCIIEncoding asen = new ASCIIEncoding();
byte[] ba = asen.GetBytes(str);
Console.WriteLine("Transmitting.....");
stm.Write(ba, 0, ba.Length);
Console.Write("Enter the string to be transmitted : ");
String str2 = Console.ReadLine();
if (str2 == "")
{
str2 = " ";
}
Stream stm2 = tcpclnt.GetStream();
ASCIIEncoding asen2 = new ASCIIEncoding();
byte[] ba2 = asen2.GetBytes(str2);
Console.WriteLine("Transmitting.....");
stm.Write(ba2, 0, ba2.Length);
if (str == "false")
{
blijvenWerken = false;
}
byte[] bb = new byte[100];
int k = stm.Read(bb, 0, 100);
for (int i = 0; i < k; i++)
Console.Write(Convert.ToChar(bb[i]));
byte[] bb2 = new byte[100];
int k2 = stm.Read(bb2, 0, 100);
Console.Write("\n");
for (int i = 0; i < k2; i++)
Console.Write(Convert.ToChar(bb2[i]));
Console.WriteLine("\n");
tcpclnt.Close();
Thread.Sleep(1000);
}
Server getting the sockets:
This bit of code is on the loginserver, its because i can only accept 1 socket every time to keep the connection alive, that i put queueCount on a maximum of 1.
I want to be able to make a list of Sockets that i accepted to add to a User account.
while (loginServerOn)
{
if (queueCount < 1)
{
if (loginServer.getLoginListener().Pending())
{
loginQueue.Add(loginServer.getSocket());
ASCIIEncoding asen = new ASCIIEncoding();
Socket s = loginQueue.First();
try
{
s.Send(asen.GetBytes("true"));
queueCount++;
}
catch
{
loginQueue.Remove(s);
}
}
}
}
The function that returns the accepted socket.
public Socket getSocket()
{
return myList.AcceptSocket();
}
EDIT: Essence of the question
I want to add the socked or client recieved to my Account object, so every connection has an Account its linked to, when i want to send a message to a certain account, it should send a message to the socked or client bound to that account, can you help/show me how i can achieve this?

This is still c# and sockets but my approach is different to yours.
I went with the concept of a "connectedCleint" which is similar in purpose to what you've called an account.
I have a class called ServerTerminal which is responsible for accepting and top level management of socket connections. In this i've got:
public Dictionary<long, ConnectedClient> DictConnectedClients =
new Dictionary<long, ConnectedClient>();
So this is my list of connected clients indexed by the sockethandle.
To accept connections i've got a routine:
public void StartListen(int port)
{
socketClosed = false;
IPEndPoint ipLocal = new IPEndPoint(IPAddress.Any, port);
listenSocket = new Socket(AddressFamily.InterNetwork,
SocketType.Stream, ProtocolType.Tcp);
//bind to local IP Address...
//if ip address is allready being used write to log
try
{
listenSocket.Bind(ipLocal);
}
catch (Exception excpt)
{
// Deal with this.. write your own log code here ?
socketClosed = true;
return;
}
//start listening...
listenSocket.Listen(100); // Max 100 connections for my app
// create the call back for any client connections...
listenSocket.BeginAccept(new AsyncCallback(OnClientConnection), null);
}
So when a client connects it then fires off:
private void OnClientConnection(IAsyncResult asyn)
{
if (socketClosed)
{
return;
}
try
{
Socket clientSocket = listenSocket.EndAccept(asyn);
ConnectedClient connectedClient = new ConnectedClient(clientSocket, this, _ServerTerminalReceiveMode);
//connectedClient.MessageReceived += OnMessageReceived;
connectedClient.Disconnected += OnDisconnection;
connectedClient.dbMessageReceived += OndbMessageReceived;
connectedClient.ccSocketFaulted += ccSocketFaulted;
connectedClient.StartListening();
long key = clientSocket.Handle.ToInt64();
if (DictConnectedClients.ContainsKey(connectedClient.SocketHandleInt64))
{
// Already here - use your own error reporting..
}
lock (DictConnectedClients)
{
DictConnectedClients[key] = connectedClient;
}
// create the call back for any client connections...
listenSocket.BeginAccept(new AsyncCallback(OnClientConnection), null);
}
catch (ObjectDisposedException excpt)
{
// Your own code here..
}
catch (Exception excpt)
{
// Your own code here...
}
}
The crucial part of this for you is:
// create the call back for any client connections...
listenSocket.BeginAccept(new AsyncCallback(OnClientConnection), null);
This sets up the serverterminal to receive new connections.
Edit:
Cut down version of my connectedclient:
public class ConnectedClient
{
private Socket mySocket;
private SocketIO mySocketIO;
private long _mySocketHandleInt64 = 0;
// These events are pass through; ConnectedClient offers them but really
// they are from SocketIO
public event TCPTerminal_ConnectDel Connected
{
add
{
mySocketIO.Connected += value;
}
remove
{
mySocketIO.Connected -= value;
}
}
public event TCPTerminal_DisconnectDel Disconnected
{
add
{
mySocketIO.Disconnected += value;
}
remove
{
mySocketIO.Disconnected -= value;
}
}
// Own Events
public event TCPTerminal_TxMessagePublished TxMessageReceived;
public delegate void SocketFaulted(ConnectedClient cc);
public event SocketFaulted ccSocketFaulted;
private void OnTxMessageReceived(Socket socket, TxMessage myTxMessage)
{
// process your message
}
private void OnMessageSent(int MessageNumber, int MessageType)
{
// successful send, do what you want..
}
public ConnectedClient(Socket clientSocket, ServerTerminal ParentST)
{
Init(clientSocket, ParentST, ReceiveMode.Handler);
}
public ConnectedClient(Socket clientSocket, ServerTerminal ParentST, ReceiveMode RecMode)
{
Init(clientSocket, ParentST, RecMode);
}
private void Init(Socket clientSocket, ServerTerminal ParentST, ReceiveMode RecMode)
{
ParentServerTerminal = ParentST;
_myReceiveMode = RecMode;
_FirstConnected = DateTime.Now;
mySocket = clientSocket;
_mySocketHandleInt64 = mySocket.Handle.ToInt64();
mySocketIO = new SocketIO(clientSocket, RecMode);
// Register for events
mySocketIO.TxMessageReceived += OnTxMessageReceived;
mySocketIO.MessageSent += OnMessageSent;
mySocketIO.dbMessageReceived += OndbMessageReceived;
}
public void StartListening()
{
mySocketIO.StartReceiving();
}
public void Close()
{
if (mySocketIO != null)
{
mySocketIO.Close();
mySocketIO = null;
}
try
{
mySocket.Close();
}
catch
{
// We're closing.. don't worry about it
}
}
public void SendMessage(int MessageNumber, int MessageType, string Message)
{
if (mySocket != null && mySocketIO != null)
{
try
{
mySocketIO.SendMessage(MessageNumber, MessageType, Message);
}
catch
{
// mySocketIO disposed inbetween check and call
}
}
else
{
// Raise socket faulted event
if (ccSocketFaulted != null)
ccSocketFaulted(this);
}
}
}
}
Some useful links:
This is where I started:
http://vadmyst.blogspot.com.au/2008/01/how-to-transfer-fixed-sized-data-with.html
http://vadmyst.blogspot.com.au/2008/03/part-2-how-to-transfer-fixed-sized-data.html
And..
C# Sockets and Multithreading
Cause a connected socket to accept new messages right after .BeginReceive?
http://nitoprograms.blogspot.com.au/2009/04/tcpip-net-sockets-faq.html
http://www.codeproject.com/Articles/83102/C-SocketAsyncEventArgs-High-Performance-Socket-Cod
I can't post my entire solution just now; there is a flaw in my server code I need to debug; plus there are parts which my employer may not want published. But i based my code on what Vadym had for variable length messages.

When a server gets ready to accept TCP connections, it creates a new TCP socket, Bind() it to a port and uses the Listen() method. When a connection request comes in, the Listen() method returns a new socket that the server and client use for communication. The server and client can pass data back and forth using Send() and Receive() at this point. If the client disconnects, the server's Receive() terminates with 0 bytes of data.
If you want to wait for another connection request once you've accepted the first connection (i.e., while you are interacting with the first client) this can be done. At this point, you'll need to use something like threads or asynchronous methods so you can handle more than one connection. Basically, you will be able to Accept() connection requests from your listening socket.
Mike