完整的udp客户端

using System;
using System.Collections.Generic;
using System.Text;
using System.Net;
using System.Net.Sockets;

namespace BestUdpClient
...{
    class Program
    ...{
        private static byte[] data = new byte[1024];
        private static IPEndPoint sender = new IPEndPoint(IPAddress.Any, 9050);
        private static EndPoint remote = (EndPoint)sender;
        private static int size = 30;
        private static int AdvSndRcvData(Socket s, byte[] message, EndPoint rmtdevice)
        ...{
            int recv = 0;
            int retry = 0;
            while (true)
            ...{
                Console.WriteLine("Attemp #{0}", retry);
                try
                ...{
                    s.SendTo(message, message.Length, SocketFlags.None, rmtdevice);
                    data = new byte[size];
                    recv = s.ReceiveFrom(data, ref remote);
                }
                catch (SocketException e)
                ...{
                    if (e.ErrorCode == 10054)
                        recv = 0;
                    else if (e.ErrorCode == 10040)
                    ...{
                        Console.WriteLine("Error receiving packet");
                        size += 10;
                        recv = 0;
                    }
                }
                if (recv > 0)
                    return recv;
                else
                ...{
                    retry++;
                    if (retry > 4)
                    ...{
                        return 0;
                    }
                }
            }
        }
        static void Main(string[] args)
        ...{
            string input, stringdata;
            int recv;
            IPEndPoint ipep = new IPEndPoint(IPAddress.Parse("127.0.0.1"), 9050);
            Socket server = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
            int sockopt = (int)server.GetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReceiveTimeout);
            Console.WriteLine("Default timeout:{0}", sockopt);
            server.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReceiveTimeout, 3000);
            sockopt = (int)server.GetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReceiveTimeout);
            Console.WriteLine("New timeout:{0}", sockopt);
            string welcome = "Hello,are you there";
            data = Encoding.ASCII.GetBytes(welcome);
            recv = AdvSndRcvData(server,data, ipep);
            if (recv > 0)
            ...{
                stringdata = Encoding.ASCII.GetString(data, 0, recv);
                Console.WriteLine(stringdata);
            }
            else
            ...{
                Console.WriteLine("Unable to communicate with remote host");
                return;
            }
            while (true)
            ...{
                input = Console.ReadLine();
                if (input == "exit")
                ...{
                    break;
                }
                recv = AdvSndRcvData(server, Encoding.ASCII.GetBytes(input), ipep);
                if (recv > 0)
                ...{
                    stringdata = Encoding.ASCII.GetString(data, 0, recv);
                    Console.WriteLine(stringdata);
                }
                else
                    Console.WriteLine("Did not receive an answer");
            }
            Console.WriteLine("Stopping  client");
            server.Close();
        }
    }
}