public   class TestConnect

    {

        string hostIp = "";

        int port = ;

        public string recMsg = "";

        Socket socketC = null;

        private readonly ManualResetEvent TimeoutObject = new ManualResetEvent(false);

       public TestConnect(string hostIp, int port)

       {

           this.hostIp = hostIp;

           this.port = port;

       }

       public bool connect()

       {

           ///创建终结点（EndPoint）

           IPAddress ip = IPAddress.Parse(hostIp);//把ip地址字符串转换为IPAddress类型的实例

           IPEndPoint ipe = new IPEndPoint(ip, port);//用指定的端口和ip初始化IPEndPoint类的新实例

           ///创建socket

           socketC = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);//创建一个socket对像，如果用udp协议，则要用SocketType.Dgram类型的套接字

           try

           {

               return Connect(ipe,);

           }

           catch (SocketException ex)

           {

               socketC.Close();

               socketC = null;

               return false;

           }

       }

       /// <summary>

       /// Socket连接请求

       /// </summary>

       /// <param name="remoteEndPoint">网络端点</param>

       /// <param name="timeoutMSec">超时时间</param>

       public bool Connect(IPEndPoint remoteEndPoint, int timeoutMSec)

       {

           TimeoutObject.Reset();

           socketC = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);

           socketC.BeginConnect(remoteEndPoint, CallBackMethod, socketC);

           //阻塞当前线程

           if (TimeoutObject.WaitOne(timeoutMSec, false))

           {

               return true;

           }

           else

           {

               return false;

           }

       }

       //--异步回调方法

       private void CallBackMethod(IAsyncResult asyncresult)

       {

           //使阻塞的线程继续

           Socket socket = asyncresult.AsyncState as Socket;

           if (socket.Connected)

            {

                socket.EndConnect(asyncresult);

            }

           TimeoutObject.Set();

       }

       public void testOnline(string msg)

       {

              socketC.Send(Encoding.GetEncoding("gb2312").GetBytes(msg));

　　　　　　try

　　　　　　{

          //创建一个通信线程

                ParameterizedThreadStart pts = new ParameterizedThreadStart(ServerRecMsg);

                Thread thr = new Thread(pts);

                thr.IsBackground = true;

                //启动线程

                thr.Start(socketC);

　　　　　　}

　　　　　　catch

　　　　　　{ throw ;}

　　　　}

　　

　　 /// <summary>

        /// 接收客户端发来的信息

        /// </summary>

        /// <param name="socketClientPara">客户端套接字对象</param>

        private void ServerRecMsg(object socketClientPara)

        {

            Socket socketServer = socketClientPara as Socket;

            byte[] arrServerRecMsg = new byte[];

            int len;

            while ((len = socketServer.Receive(arrServerRecMsg)) != )

            {

                //将机器接受到的字节数组转换为人可以读懂的字符串

                recMsg = Encoding.Default.GetString(arrServerRecMsg, , len);

                if (recMsg == "online")

                {

                    break;

                }

            }

        }

    }