关于WEB服务代理

这是一个服务代理的简单类：  
    class proxy
    {
        private Socket clientSocket;
        byte[] read = new byte[1024];
        byte[] buffer = null;
        Encoding ASCII = Encoding.ASCII;
        byte[] RecvBytes = new byte[4096];
        public proxy(Socket s)
        {
            this.clientSocket = s;
        }
        public void Run()
        {
            string clientmessage = " ";
            //存放来自客户端的HTTP请求字符串
            string URL = " ";
            //存放解析出地址请求信息
            int bytes = ReadMessage(read, ref clientSocket, ref clientmessage);
            if (bytes == 0)
            {
                return;
            }
            int index1 = clientmessage.IndexOf(' ');
            int index2 = clientmessage.IndexOf(' ', index1 + 1);
            if ((index1 == -1) || (index2 == -1))
            {
                throw new IOException();
            }
            string part1 = clientmessage.Substring(index1 + 1, index2 - index1);
            int index3 = part1.IndexOf('/', index1 + 8);
            int index4 = part1.IndexOf(' ', index1 + 8);
            int index5 = index4 - index3;
            URL = part1.Substring(index1 + 4, (part1.Length - index5) - 8);
            try
            {
                IPHostEntry IPHost = Dns.Resolve(URL);
                Console.WriteLine("远程主机名： " + IPHost.HostName);
                string[] aliases = IPHost.Aliases;
                IPAddress[] address = IPHost.AddressList;
                Console.WriteLine("Web服务器IP地址：" + address[0]);
                //解析出要访问的服务器地址
                IPEndPoint ipEndpoint = new IPEndPoint(address[0], 80);
                Socket IPsocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
                //创建连接Web服务器端的Socket对象
                IPsocket.Connect(ipEndpoint);
                //Socket连Web接服务器
                if (IPsocket.Connected)
                    Console.WriteLine("Socket 正确连接！");
                string GET = clientmessage;
                Byte[] ByteGet = ASCII.GetBytes(GET);
                IPsocket.Send(ByteGet, ByteGet.Length, 0);
                //代理访问软件对服务器端传送HTTP请求命令
                Int32 rBytes = IPsocket.Receive(RecvBytes, RecvBytes.Length, 0);
                //代理访问软件接收来自Web服务器端的反馈信息
                Console.WriteLine("接收字节数：" + rBytes.ToString());
                String strRetPage = null;
                strRetPage = strRetPage + ASCII.GetString(RecvBytes, 0, rBytes);
                while (rBytes > 0)
                {
                    rBytes = IPsocket.Receive(RecvBytes, RecvBytes.Length, 0);
                    strRetPage = strRetPage + ASCII.GetString(RecvBytes, 0, rBytes);
                }
                IPsocket.Shutdown(SocketShutdown.Both);
                IPsocket.Close();
                SendMessage(clientSocket, strRetPage);
                //代理服务软件往客户端传送接收到的信息
            }
            catch (Exception exc2)
            {
                Console.WriteLine(exc2.ToString());
            }
        }
        //接收客户端的HTTP请求数据
        private int ReadMessage(byte[] ByteArray, ref Socket s, ref String clientmessage)
        {
            int bytes = s.Receive(ByteArray, 1024, 0);
            string messagefromclient = Encoding.ASCII.GetString(ByteArray);
            clientmessage = (String)messagefromclient;
            return bytes;
        }        //传送从Web服务器反馈的数据到客户端
        private void SendMessage(Socket s, string message)
        {
            buffer = new Byte[message.Length + 1];
            int length = ASCII.GetBytes(message, 0, message.Length, buffer, 0);
            Console.WriteLine("传送字节数：" + length.ToString());
            s.Send(buffer, length, 0);
        }
    }
在解析URL的时候，遇到了一堆string.indexof，想问一问一般客户向服务器发送的请求是什么格式的？
另外，里面的一句：DNS.solve()说已经过时，请问它有什么不好？应该用什么才不过时？
谢谢了！