using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Threading.Tasks;using System.Net.Sockets;namespace ConsoleApplication5{    class Program    {        static void Main(string[] args)        {            Socket s = new Socket(SocketType.Stream, ProtocolType.Tcp);            String host = "qq.com";            int port = 80;            byte[] buf = null;            s.Connect(host, port);            string text = "hi";            buf = Encoding.Default.GetBytes(text);            int len = s.Send(buf);            buf = new byte[1024];            len = s.Receive(buf);            string resp = Encoding.Default.GetString(buf);            s.Close();            System.Console.WriteLine(resp);            System.Console.ReadKey();        }    }}