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using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net;
using System.Net.Sockets;
using System.Threading;
namespace ConsoleApplication48
{
class Program
{
public class StateObject {
// Client socket.
public Socket workSocket = null;
// Size of receive buffer.
public const int BufferSize = 256;
// Receive buffer.
public byte[] buffer = new byte[BufferSize];
// Received data string.
public StringBuilder sb = new StringBuilder();
}
public class AsynchronousClient
{
// The port number for the remote device.
private const int port = 1200;
// ManualResetEvent instances signal completion.
private static ManualResetEvent connectDone =
new ManualResetEvent(false);
private static ManualResetEvent sendDone =
new ManualResetEvent(false);
private static ManualResetEvent receiveDone =
new ManualResetEvent(false);
// The response from the remote device.
private static String response = String.Empty;
private static void StartClient()
{
// Connect to a remote device.
try
{
string LocalHostName = Dns.GetHostName();
IPHostEntry LocalHostIPEntry = Dns.GetHostEntry(LocalHostName); ;
IPAddress ipAddress = LocalHostIPEntry.AddressList.Where(x => !x.IsIPv6LinkLocal).FirstOrDefault();
IPEndPoint remoteEP = new IPEndPoint(ipAddress, port);
// Create a TCP/IP socket.
Socket client = new Socket(ipAddress.AddressFamily,
SocketType.Stream, ProtocolType.Tcp);
// Connect to the remote endpoint.
client.BeginConnect(remoteEP,
new AsyncCallback(ConnectCallback), client);
connectDone.WaitOne();
// Send data to the remote device.
Send(client, "HELLO");
sendDone.WaitOne();
while (true)
{
Receive(client);
receiveDone.WaitOne();
if (!string.IsNullOrWhiteSpace(response))
Console.WriteLine(response);
}
// Release the socket.
client.Shutdown(SocketShutdown.Both);
client.Close();
}
catch (Exception e)
{
Console.WriteLine(e.ToString());
}
}
private static void ConnectCallback(IAsyncResult ar)
{
// Retrieve the socket from the state object.
Socket client = (Socket)ar.AsyncState;
// Complete the connection.
client.EndConnect(ar);
Console.WriteLine("Socket connected to {0}",
client.RemoteEndPoint.ToString());
// Signal that the connection has been made.
connectDone.Set();
}
private static void Receive(Socket client)
{
// Create the state object.
StateObject state = new StateObject();
state.workSocket = client;
// Begin receiving the data from the remote device.
client.BeginReceive(state.buffer, 0, StateObject.BufferSize, 0,
new AsyncCallback(ReceiveCallback), state);
}
private static void ReceiveCallback(IAsyncResult ar)
{
// Retrieve the state object and the client socket
// from the asynchronous state object.
StateObject state = (StateObject)ar.AsyncState;
Socket client = state.workSocket;
// Read data from the remote device.
int bytesRead = client.EndReceive(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));
Send(client, "HELLO");
// Get the rest of the data.
client.BeginReceive(state.buffer, 0, StateObject.BufferSize, 0,
new AsyncCallback(ReceiveCallback), state);
}
else
{
// All the data has arrived; put it in response.
if (state.sb.Length > 1)
{
response = state.sb.ToString();
}
// Signal that all bytes have been received.
receiveDone.Set();
}
}
private static void Send(Socket client, 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.
client.BeginSend(byteData, 0, byteData.Length, 0,
new AsyncCallback(SendCallback), client);
}
private static void SendCallback(IAsyncResult ar)
{
// Retrieve the socket from the state object.
Socket client = (Socket)ar.AsyncState;
// Complete sending the data to the remote device.
int bytesSent = client.EndSend(ar);
Console.WriteLine("Sent {0} bytes to server.", bytesSent);
// Signal that all bytes have been sent.
sendDone.Set();
}
public static void AcceptCallback(IAsyncResult ar) {
// Signal the main thread to continue.
// Get the socket that handles the client request.
TcpListener listener = (TcpListener) ar.AsyncState;
Socket handler = listener.Server.EndAccept(ar);
// Create the state object.
StateObject state = new StateObject();
state.workSocket = handler;
handler.BeginReceive( state.buffer, 0, StateObject.BufferSize, 0,
new AsyncCallback(ListenerReadCallback), state);
}
public static void ListenerReadCallback(IAsyncResult 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.workSocket;
// Read data from the client socket.
int bytesRead = handler.EndReceive(ar);
if (bytesRead > 0) {
handler.BeginSend(state.buffer, 0, bytesRead, 0,
new AsyncCallback(ListenerSendCallback), handler);
}
// Not all data received. Get more.
handler.BeginReceive(state.buffer, 0, StateObject.BufferSize, 0,
new AsyncCallback(ListenerReadCallback), state);
}
private static void ListenerSendCallback(IAsyncResult ar) {
Socket handler = (Socket)ar.AsyncState;
int bytesSent = handler.EndSend(ar);
}
static void Main(string[] args)
{
TcpListener listener = new TcpListener(IPAddress.Any, 1200);
listener.Start();
listener.Server.BeginAccept(
new AsyncCallback(AcceptCallback),
listener );
StartClient();
}
}
}
}