BeginAccept(AsyncCallback AsyncCallback, Ojbect state)

//定义IP地址
IPAddress local = IPAddress.Parse("127.0,0,1");
IPEndPoint iep = new IPEndPoint(local,13000);
//创建服务器的socket对象
Socket server = new Socket(AddressFamily.InterNetwork,SocketType.Stream,ProtocolType.Tcp);
server.Bind(iep);
server.Listen(20);
server.BeginAccecpt(new AsyncCallback(Accept),server);

void Accept(IAsyncResult iar)
{
    //还原传入的原始套接字
    Socket MyServer = (Socket)iar.AsyncState;
    //在原始套接字上调用EndAccept方法，返回新的套接字
    Socket service = MyServer.EndAccept(iar);
}

Socket socket=new Socket(AddressFamily.InterNetwork,SocketType.Stream,ProtocolType.Tcp)
IPAddress ip=IPAddress.Parse("127.0.0.1");
IPEndPoint iep=new IPEndPoint(ip,13000);
socket.BeginConnect(iep, new AsyncCallback(Connect),socket);

void Connect(IAsyncResult iar)
{
    Socket client=(Socket)iar.AsyncState;
    try
    {
        client.EndConnect(iar);
    }
    catch (Exception e)
    {
        Console.WriteLine(e.ToString());
    }
    finally
    {

    }
}

public static void DoBeginAccept(TcpListener listner)
{
    //开始从客户端监听连接
    Console.WriteLine("Waitting for a connection");
    //接收连接
    //开始准备接入新的连接，一旦有新连接尝试则调用回调函数DoAcceptTcpCliet
    listner.BeginAcceptTcpClient(new AsyncCallback(DoAcceptTcpCliet), listner);
}

//处理客户端的连接
public static void DoAcceptTcpCliet(IAsyncResult iar)
{
    //还原原始的TcpListner对象
    TcpListener listener = (TcpListener)iar.AsyncState;

    //完成连接的动作，并返回新的TcpClient
    TcpClient client = listener.EndAcceptTcpClient(iar);
    Console.WriteLine("连接成功");
}

public void doBeginConnect(IAsyncResult iar)
{
    Socket client=(Socket)iar.AsyncState;
    //开始与远程主机进行连接
    client.BeginConnect(serverIP[0],13000,requestCallBack,client);
    Console.WriteLine("开始与服务器进行连接");
}
private void requestCallBack(IAsyncResult iar)
{
    try
    {
        //还原原始的TcpClient对象
        TcpClient client=(TcpClient)iar.AsyncState;
        //
        client.EndConnect(iar);
        Console.WriteLine("与服务器{0}连接成功",client.Client.RemoteEndPoint);
    }
    catch(Exception e)
    {
        Console.WriteLine(e.ToString());
    }
    finally
    {

    }
}

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.BeginSend(byteData, 0, byteData.Length, 0, new AsyncCallback(SendCallback), handler);
}
private static void SendCallback(IAsyncResult 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.WriteLine("Sent {0} bytes to client.", bytesSent);
        handler.Shutdown(SocketShutdown.Both);
        handler.Close();
    }
    catch (Exception e)
    {
        Console.WriteLine(e.ToString());
    }
}

private static void Receive(Socket client)
{
    try
    {
        // 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);
    }
    catch (Exception e)
    {
        Console.WriteLine(e.ToString());
    }
}
private static void ReceiveCallback(IAsyncResult ar)
{
    try
    {
        // 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));
            // 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();
        }
    }
    catch (Exception e)
    {
        Console.WriteLine(e.ToString());
    }
}

static void DataHandle(TcpClient client)
{
  TcpClient tcpClient = client;
  //使用TcpClient的GetStream方法获取网络流
  NetworkStream ns = tcpClient.GetStream();
  //检查网络流是否可读
  if(ns.CanRead)
  {
    //定义缓冲区
    byte[] read = new byte[1024];
    ns.BeginRead(read,0,read.Length,new AsyncCallback(myReadCallBack),ns);  
  }
  else
  {
    Console.WriteLine("无法从网络中读取流数据");
  }
}

public static void myReadCallBack(IAsyncResult iar)
{
    NetworkStream ns = (NetworkStream)iar.AsyncState;
    byte[] read = new byte[1024];
    String data = "";
    int recv;

    recv = ns.EndRead(iar);
    data = String.Concat(data, Encoding.ASCII.GetString(read, 0, recv));

    //接收到的消息长度可能大于缓冲区总大小，反复循环直到读完为止
    while (ns.DataAvailable)
    {
        ns.BeginRead(read, 0, read.Length, new AsyncCallback(myReadCallBack), ns);
    }
    //打印
    Console.WriteLine("您收到的信息是" + data);
}

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.com".     
    //IPHostEntry ipHostInfo = Dns.Resolve(Dns.GetHostName());
    //IPAddress ipAddress = ipHostInfo.AddressList[0];
    IPAddress ipAddress = IPAddress.Parse("127.0.0.1");
    IPEndPoint localEndPoint = new IPEndPoint(ipAddress, 11000);
    // Create a TCP/IP socket.     
    Socket listener = new Socket(AddressFamily.InterNetwork,SocketType.Stream, ProtocolType.Tcp);
    // Bind the socket to the local     
    //endpoint and listen for incoming connections.     
    try
    {
        listener.Bind(localEndPoint);
        listener.Listen(100);
        while (true)
        {
            // Set the event to nonsignaled state.     
            allDone.Reset();
            // Start an asynchronous socket to listen for connections.     
            Console.WriteLine("Waiting for a connection...");
            listener.BeginAccept(new AsyncCallback(AcceptCallback),listener);
            // Wait until a connection is made before continuing.     
            allDone.WaitOne();
        }
    }
    catch (Exception e)
    {
        Console.WriteLine(e.ToString());
    }
    Console.WriteLine("\nPress ENTER to continue...");
    Console.Read();
}