贴一些C#代码 因为公司禁止对外通信解决方案

    public delegate void ExceptionEventHandler(object sender, Exception e);    public delegate void SocketExceptionEventHandler(object sender, System.Net.Sockets.SocketException e);    public delegate void ReceiveDataEventHandler(object sender, byte[] data);    public delegate void SocketCloseEventHandler(object sender,System.Net.Sockets.Socket sock);

public class Common    {        public static IPEndPoint GetEPByName(string HostName,int Port)        {            IPEndPoint ep = null;            foreach (IPAddress ip in Dns.GetHostAddresses(HostName))            {                if (ip.AddressFamily == AddressFamily.InterNetwork)                {                    ep = new IPEndPoint(ip, Port);                    break;                }            }            return ep;        }        /// <summary>        /// 使用已连接的Socket接收数据        /// </summary>        /// <param name="sock">已连接的Socket</param>        /// <param name="ReceiveLength">将要接收的数据长度</param>        /// <returns>返回接受到的数据，若对方关闭连接则返回null</returns>        public static byte[] ReceiveData(Socket sock,int ReceiveLength)        {             byte[] buff = new byte[ReceiveLength];            int readbytes = 0;            try            {                while (ReceiveLength != 0)                {                    readbytes = sock.EndReceive(sock.BeginReceive(buff, buff.Length - ReceiveLength, ReceiveLength, SocketFlags.None, null, null));                    if (readbytes <= 0)                        return new byte[0];                    ReceiveLength -= readbytes;                }                return buff;            } catch (Exception e){ throw e; }        }        /// <summary>        /// 使用已连接的Socket发送数据        /// </summary>        /// <param name="sock">已连接的Socket</param>        /// <param name="data">将要发送的数据</param>        /// <returns>返回数据是否发送成功</returns>        public static bool SendData(Socket sock,byte[] data)        {            int SendLength = 0;            int sendbytes = 0;            try            {                while (SendLength != data.Length)                {                    sendbytes = sock.EndSend(sock.BeginSend(data, SendLength, data.Length - SendLength, SocketFlags.None, null, null));                    if (sendbytes <= 0)                        return false;                    SendLength += sendbytes;                }                return true;            } catch (Exception e) { throw e; }        }    }

public class Listener    {        public event ExceptionEventHandler OnException;        public event ReceiveDataEventHandler OnReceiveData;        public event SocketExceptionEventHandler OnSocketException;        public event SocketCloseEventHandler OnSocketClose;        Socket listener = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);        public Listener()        {            OnSocketClose += new SocketCloseEventHandler(Listener_OnSocketClose);        }        /// <summary>        /// 这个方法或许不对，有疑问        /// </summary>        public void StopListening()        {            listener.Close();        }        public void StartListening(int Port,int backlog)        {            try            {                listener.Bind(Common.GetEPByName(Environment.MachineName, Port));                listener.Listen(backlog);                listener.BeginAccept(new AsyncCallback(AcceptCallback), listener);            }            catch (SocketException e)            {                if (OnSocketException != null)                    OnSocketException(this, e);            }            catch (Exception e)            {                if (OnException != null)                    OnException(this, e);            }        }        void AcceptCallback(IAsyncResult ar)        {            try            {                Socket listener = (Socket)ar.AsyncState;                Socket handler = listener.EndAccept(ar);                listener.BeginAccept(new AsyncCallback(AcceptCallback), listener);                while (true)                {                    byte[] LengthBuff = Common.ReceiveData(handler, 4);                    if (LengthBuff.Length == 0)                        OnSocketClose(this, handler);                    byte[] DataBuff = Common.ReceiveData(handler, BitConverter.ToInt32(LengthBuff, 0));                    if (DataBuff.Length == 0)                        OnSocketClose(this, handler);                    if (OnReceiveData != null)                        OnReceiveData(this, DataBuff);                }            }            catch (SocketException e)            {                if (OnSocketException != null)                    OnSocketException(this, e);            }            catch (Exception e)            {                if (OnException != null)                    OnException(this, e);            }        }        void Listener_OnSocketClose(object sender, Socket sock)        {            try            {                sock.Shutdown(SocketShutdown.Both);            }            finally            {                sock.Close();            }        }            }