My app has an asynchronous socket server. It will have 20 clients connected
to the server. Each client sends data every 500 millisecondsThe Connections
once established will not be closed unless there is a problem with the
connection.
I need to know which client has sent the incoming data as each client has
its own buffer on my "server" app.
I am using the standard asynch socket code from MSDN to listen for
connections and they process their data as shown below.
My question is :- As my connections are permanent once established is there
a way in the read callback function to identify from which client the data
has come from?
using System;
using System.Net;
using System.Net.Sock ets;
using System.Text;
using System.Threadin g;
// State object for reading client data asynchronously
public class StateObject {
// Client socket.
public Socket workSocket = null;
// Size of receive buffer.
public const int BufferSize = 1024;
// Receive buffer.
public byte[] buffer = new byte[BufferSize];
// Received data string.
public StringBuilder sb = new StringBuilder() ;
}
public class AsynchronousSoc ketListener {
// Thread signal.
public static ManualResetEven t allDone = new ManualResetEven t(false);
public AsynchronousSoc ketListener() {
}
public static void StartListening( ) {
// Data buffer for incoming data.
byte[] bytes = new Byte[1024];
// Establish the local endpoint for the socket.
// The DNS name of the computer
// running the listener is "host.contoso.c om".
IPHostEntry ipHostInfo = Dns.Resolve(Dns .GetHostName()) ;
IPAddress ipAddress = ipHostInfo.Addr essList[0];
IPEndPoint localEndPoint = new IPEndPoint(ipAd dress, 11000);
// Create a TCP/IP socket.
Socket listener = new Socket(AddressF amily.InterNetw ork,
SocketType.Stre am, ProtocolType.Tc p );
// Bind the socket to the local endpoint and listen for incoming
connections.
try {
listener.Bind(l ocalEndPoint);
listener.Listen (100);
while (true) {
// Set the event to nonsignaled state.
allDone.Reset() ;
// Start an asynchronous socket to listen for connections.
Console.WriteLi ne("Waiting for a connection...") ;
listener.BeginA ccept(
new AsyncCallback(A cceptCallback),
listener );
// Wait until a connection is made before continuing.
allDone.WaitOne ();
}
} catch (Exception e) {
Console.WriteLi ne(e.ToString() );
}
Console.WriteLi ne("\nPress ENTER to continue...");
Console.Read();
}
public static void AcceptCallback( IAsyncResult ar) {
// Signal the main thread to continue.
allDone.Set();
// Get the socket that handles the client request.
Socket listener = (Socket) ar.AsyncState;
Socket handler = listener.EndAcc ept(ar);
// Create the state object.
StateObject state = new StateObject();
state.workSocke t = handler;
handler.BeginRe ceive( state.buffer, 0, StateObject.Buf ferSize, 0,
new AsyncCallback(R eadCallback), state);
}
public static void ReadCallback(IA syncResult ar) {
String content = String.Empty;
// Retrieve the state object and the handler socket
// from the asynchronous state object.
StateObject state = (StateObject) ar.AsyncState;
Socket handler = state.workSocke t;
// Read data from the client socket.
int bytesRead = handler.EndRece ive(ar);
if (bytesRead > 0) {
// There might be more data, so store the data received so far.
state.sb.Append (Encoding.ASCII .GetString(
state.buffer,0, bytesRead));
// Check for end-of-file tag. If it is not there, read
// more data.
content = state.sb.ToStri ng();
if (content.IndexO f("<EOF>") > -1) {
// All the data has been read from the
// client. Display it on the console.
Console.WriteLi ne("Read {0} bytes from socket. \n Data : {1}",
content.Length, content );
// Echo the data back to the client.
Send(handler, content);
} else {
// Not all data received. Get more.
handler.BeginRe ceive(state.buf fer, 0,
StateObject.Buf ferSize, 0,
new AsyncCallback(R eadCallback), state);
}
}
}
private static void Send(Socket handler, String data) {
// Convert the string data to byte data using ASCII encoding.
byte[] byteData = Encoding.ASCII. GetBytes(data);
// Begin sending the data to the remote device.
handler.BeginSe nd(byteData, 0, byteData.Length , 0,
new AsyncCallback(S endCallback), handler);
}
private static void SendCallback(IA syncResult ar) {
try {
// Retrieve the socket from the state object.
Socket handler = (Socket) ar.AsyncState;
// Complete sending the data to the remote device.
int bytesSent = handler.EndSend (ar);
Console.WriteLi ne("Sent {0} bytes to client.", bytesSent);
handler.Shutdow n(SocketShutdow n.Both);
handler.Close() ;
} catch (Exception e) {
Console.WriteLi ne(e.ToString() );
}
}
public static int Main(String[] args) {
StartListening( );
return 0;
}
}
Thanks In Advance,
Macca
to the server. Each client sends data every 500 millisecondsThe Connections
once established will not be closed unless there is a problem with the
connection.
I need to know which client has sent the incoming data as each client has
its own buffer on my "server" app.
I am using the standard asynch socket code from MSDN to listen for
connections and they process their data as shown below.
My question is :- As my connections are permanent once established is there
a way in the read callback function to identify from which client the data
has come from?
using System;
using System.Net;
using System.Net.Sock ets;
using System.Text;
using System.Threadin g;
// State object for reading client data asynchronously
public class StateObject {
// Client socket.
public Socket workSocket = null;
// Size of receive buffer.
public const int BufferSize = 1024;
// Receive buffer.
public byte[] buffer = new byte[BufferSize];
// Received data string.
public StringBuilder sb = new StringBuilder() ;
}
public class AsynchronousSoc ketListener {
// Thread signal.
public static ManualResetEven t allDone = new ManualResetEven t(false);
public AsynchronousSoc ketListener() {
}
public static void StartListening( ) {
// Data buffer for incoming data.
byte[] bytes = new Byte[1024];
// Establish the local endpoint for the socket.
// The DNS name of the computer
// running the listener is "host.contoso.c om".
IPHostEntry ipHostInfo = Dns.Resolve(Dns .GetHostName()) ;
IPAddress ipAddress = ipHostInfo.Addr essList[0];
IPEndPoint localEndPoint = new IPEndPoint(ipAd dress, 11000);
// Create a TCP/IP socket.
Socket listener = new Socket(AddressF amily.InterNetw ork,
SocketType.Stre am, ProtocolType.Tc p );
// Bind the socket to the local endpoint and listen for incoming
connections.
try {
listener.Bind(l ocalEndPoint);
listener.Listen (100);
while (true) {
// Set the event to nonsignaled state.
allDone.Reset() ;
// Start an asynchronous socket to listen for connections.
Console.WriteLi ne("Waiting for a connection...") ;
listener.BeginA ccept(
new AsyncCallback(A cceptCallback),
listener );
// Wait until a connection is made before continuing.
allDone.WaitOne ();
}
} catch (Exception e) {
Console.WriteLi ne(e.ToString() );
}
Console.WriteLi ne("\nPress ENTER to continue...");
Console.Read();
}
public static void AcceptCallback( IAsyncResult ar) {
// Signal the main thread to continue.
allDone.Set();
// Get the socket that handles the client request.
Socket listener = (Socket) ar.AsyncState;
Socket handler = listener.EndAcc ept(ar);
// Create the state object.
StateObject state = new StateObject();
state.workSocke t = handler;
handler.BeginRe ceive( state.buffer, 0, StateObject.Buf ferSize, 0,
new AsyncCallback(R eadCallback), state);
}
public static void ReadCallback(IA syncResult ar) {
String content = String.Empty;
// Retrieve the state object and the handler socket
// from the asynchronous state object.
StateObject state = (StateObject) ar.AsyncState;
Socket handler = state.workSocke t;
// Read data from the client socket.
int bytesRead = handler.EndRece ive(ar);
if (bytesRead > 0) {
// There might be more data, so store the data received so far.
state.sb.Append (Encoding.ASCII .GetString(
state.buffer,0, bytesRead));
// Check for end-of-file tag. If it is not there, read
// more data.
content = state.sb.ToStri ng();
if (content.IndexO f("<EOF>") > -1) {
// All the data has been read from the
// client. Display it on the console.
Console.WriteLi ne("Read {0} bytes from socket. \n Data : {1}",
content.Length, content );
// Echo the data back to the client.
Send(handler, content);
} else {
// Not all data received. Get more.
handler.BeginRe ceive(state.buf fer, 0,
StateObject.Buf ferSize, 0,
new AsyncCallback(R eadCallback), state);
}
}
}
private static void Send(Socket handler, String data) {
// Convert the string data to byte data using ASCII encoding.
byte[] byteData = Encoding.ASCII. GetBytes(data);
// Begin sending the data to the remote device.
handler.BeginSe nd(byteData, 0, byteData.Length , 0,
new AsyncCallback(S endCallback), handler);
}
private static void SendCallback(IA syncResult ar) {
try {
// Retrieve the socket from the state object.
Socket handler = (Socket) ar.AsyncState;
// Complete sending the data to the remote device.
int bytesSent = handler.EndSend (ar);
Console.WriteLi ne("Sent {0} bytes to client.", bytesSent);
handler.Shutdow n(SocketShutdow n.Both);
handler.Close() ;
} catch (Exception e) {
Console.WriteLi ne(e.ToString() );
}
}
public static int Main(String[] args) {
StartListening( );
return 0;
}
}
Thanks In Advance,
Macca
Comment