echoclienttcp.cs

在Echo服务器上的多线程问题

using System;
using System.IO;
using System.Text;
using System.Net;
using System.Net.Sockets;

class EchoClientTcp
{
   public static void Main(String[] args)
   {
      //声明欲放置网络传输流对象的变量
      NetworkStream NetStream = null;
      //从命令行读取Echo服务器的IP地址并产生一个IPAddress对象
      IPAddress HostAddr = IPAddress.Parse(args[0]);
      //根据IP地址及通信端口7产生一IPEndPoint对象
      IPEndPoint host = new IPEndPoint(HostAddr,7);

      //产生一相对于本地端IP地址的IPAddress对象
      IPAddress LocalAddr = IPAddress.Parse("127.0.0.1");
      //根据IP地址及通信端口号13产生一IPEndPoint对象
      IPEndPoint local = new IPEndPoint(LocalAddr,13);
      //产生TcpClient对象
      TcpClient client = new TcpClient(local);
      //设置打开延迟关闭连接选项，时间为3秒
      client.LingerState = new LingerOption(true,3);

      try
      {
         //连接到所指定的服务器
         client.Connect(host);
      } 
      catch(SocketException se)
      {
          //若无法创建连接则显示出错误信息并退出程序
          Console.WriteLine("Could not establish connection to echo server!!");
          return;
      }
      //显示出成功连接的信息
      Console.WriteLine("Successfully establish connection to echo server!!");
    
      //向TcpClient对象获取网络传输流
      NetStream = client.GetStream();
      String tmpstr = "";
      while(true)
      {
         //从命令行读取用户所输入的字符串
         tmpstr = Console.ReadLine();
         //若用户输入exit则退出循环
         if (tmpstr.Equals("exit"))
             break;
   
         //将用户所输入的字符串转换为Byte数组以便发送
         Byte[] SendBytes = Encoding.ASCII.GetBytes(tmpstr.ToCharArray());
         try
         {
            //把数据发送给Echo服务器
            NetStream.Write(SendBytes,0,SendBytes.Length);
         }
         catch(IOException ioe)
         {
             Console.WriteLine("Data write error!!");
             continue;
         }

         int  bytes = 0;
         //声明一个Byte数组，稍后用来存放所接收到的数据
         Byte[] RecvBytes = new byte[256];
         String RecvString = "";
         try
         {
            //从网络传输流中读取数据，并存放在RecvBytes数组中
            bytes = NetStream.Read(RecvBytes,0,RecvBytes.Length);
         }
         catch(IOException ioe)
         {
            Console.WriteLine("Data Read error!!");
            continue;
         }
         //将Byte类型的数组转换为字符串
         RecvString = Encoding.ASCII.GetString(RecvBytes,0,bytes);
         //显示出所接收的数据
         Console.WriteLine(RecvString);
      }
      //关闭网络传输流
      NetStream.Close();
      //关闭与Echo服务器的连接
      client.Close();
   }
}