[C#]UDP 기본 에코서버클라이언트

--에코서버--

 

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
//추가한 네임스페이스
using System.Net;
using System.Net.Sockets;

namespace UdpEchoServer
{
    class Program
    {
        //포트번호
        const int ServerPortNumber = 5432;

        static void Main(string[] args)
        {
            try
            {
                //UDP Socket 만들기
                Socket udpSocket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram,
                    ProtocolType.Udp);

                // udpSocket.SetSocketOption(SocketOptionLevel.Socket,
                //         SocketOptionName.UseLoopback, true);

                //소켓에 종단점 연결
                EndPoint localEP = new IPEndPoint(IPAddress.Any, ServerPortNumber);

                //원격 호스트의 종단점을 얻어오기 위한 임시 중단점
                EndPoint remoteEP = new IPEndPoint(IPAddress.None, ServerPortNumber);

                //소켓에 중단점 바인딩
                udpSocket.Bind(localEP);

                //받기 위한 버퍼 설정
                byte[] receiveBuffer = new byte[512];
                try
                {
                    while (true)
                    {

                        receiveBuffer = new byte[512];

                        //데이터를 버퍼에 받아오며, 원격 호스트의 종단점을 알아온다.
                        int receivedSize = udpSocket.ReceiveFrom(receiveBuffer,
                            ref remoteEP);

                        string temp = Encoding.UTF8.GetString(receiveBuffer);
                        string temp2 ="";

                        temp2 = temp.Substring(0, receivedSize);
                       

                        Console.WriteLine(temp2);

                        //바로 데이터를 보냄
                        udpSocket.SendTo(receiveBuffer,
                            receivedSize, SocketFlags.None, remoteEP);
                    }
                }
                catch (Exception e)
                {
                    Console.WriteLine(e.ToString());
                }
                finally
                {
                    udpSocket.Close();
                }

            }
            catch (Exception e)
            {
                Console.WriteLine(e.ToString());
            }

        }
    }
}

 

 

--에코 클라이언트--

 

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
//추가한 네임스페이스
using System.Net;
using System.Net.Sockets;

namespace UdpEchoClient
{
    class Program
    {
        const int ServerPortNumber = 5432;

        static void Main(string[] args)
        {

            try
            {
                //UDP소켓 생성
                Socket udpSocket = new Socket(AddressFamily.InterNetwork,
                    SocketType.Dgram , ProtocolType.Udp);

                //소켓에 종단점 연결
                EndPoint localEP = new IPEndPoint(IPAddress.Any, 0);
                //임시적으로 루프백 사용
                EndPoint remoteEP = new IPEndPoint(IPAddress.Loopback,
                    ServerPortNumber);
                //바인딩
                udpSocket.Bind(localEP);

                string temp = "";

                while (temp != "exit")//데이터 전송
                {
                    byte[] sendBuffer;

                    Console.Write("전송할 데이터 입력 : ");

                    temp = Console.ReadLine();

                    sendBuffer = Encoding.UTF8.GetBytes(temp);
                    //소켓을 이용해 서버로 문자열을 보낸다.
                    udpSocket.SendTo(sendBuffer, remoteEP);

                    //데이터 수신
                    byte[] receiveBuffer = new byte[512];
                    int receiveSize = udpSocket.ReceiveFrom(receiveBuffer,
                        ref remoteEP);

                    //받아온 내용을 화면에 출력
                    Console.WriteLine(Encoding.UTF8.GetString(receiveBuffer, 0,
                        receiveSize));
                }

                udpSocket.Close();

            }
            catch(SocketException se)
            {
                Console.WriteLine(se.ToString());
            }
        }
    }
}