c# UDP odbieranie danych

 
        private void button1_Click(object sender, EventArgs e)
        {
             
             RemoteIpEndPoint = new IPEndPoint(IPAddress.Parse(textBox1.Text), 28127);
           //  RemoteIpEndPoint = new IPEndPoint(IPAddress.Any, 0);
             udpClient.Connect(RemoteIpEndPoint);

            if (nas == false)
            {   
                button1.Text = "Rozłącz";
                nas = true;
                udpClient.BeginReceive(new AsyncCallback(Odbieranie), udpClient);     
            }
            else
            {
                button1.Text = "Nasłuchuj";          
                nas = false;
            }

        }
        void Odbieranie(IAsyncResult t) 
        {

            MessageBox.Show(RemoteIpEndPoint.Address.ToString()+ " " +RemoteIpEndPoint.Port.ToString());
            Byte[] receivedBytes = udpClient.EndReceive(t, ref RemoteIpEndPoint); 
            returnData = Encoding.ASCII.GetString(receivedBytes);
            returnData = RemoteIpEndPoint.Address.ToString() + " : " + RemoteIpEndPoint.Port.ToString() + " : " + returnData;
            MessageBox.Show(returnData);
            messageReceived = true;
           

        }
    void SendData() 
        {            udpClient.BeginSend(Pocket, Pocket.Length, new AsyncCallback(Wyslano), udpClient);
            while (!messageSent)
            {
                Thread.Sleep(100);
            }
         }
        void Wyslano(IAsyncResult t)
        {
       
            MessageBox.Show("wyslano  " + udpClient.EndSend(t).ToString());
            messageSent = true;
        }

 using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Net;
using System.Net.Sockets;
using System.Threading;

namespace UDP2
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }


        UdpClient client = new UdpClient(28126);
        byte[] odb;
        string Sodb = "Start  ";
        delegate string SetValue();
        bool nas = false;
       

        void ReciveData()
        {
            while (true) 
            {
                try
                {

                    IPEndPoint anyIP = new IPEndPoint(IPAddress.Any, 0);
                    Wstaw();
                    odb = client.Receive(ref anyIP);
                    MessageBox.Show("w");
                    Sodb = Encoding.ASCII.GetString(odb);
                    Sodb = anyIP.Address.ToString() + " : " + anyIP.Port.ToString() + " : " + odb;
                    Wstaw();
                 
                }
                catch (Exception er)
                {
                    MessageBox.Show(er.ToString());
                }
            }
  
        }
        private string Wstaw()
        {
            return (string)Invoke(new SetValue(wstawianie));
        }
        private string wstawianie()
        {
            richTextBox1.AppendText(Sodb);
            richTextBox1.ScrollToCaret();


            return Sodb;
        }

        private void button1_Click(object sender, EventArgs e)
        {
            SendData();
        }


        void SendData()
        {

            byte[] lc = new byte[4];
            byte[] pocketNr = new byte[4];
            byte[] pocketDl = new byte[2];
            byte[] reserv = new byte[2]; // ---00
            byte[] Instr = new byte[4];


            IPEndPoint Cel = new IPEndPoint(IPAddress.Parse(textBox1.Text), 28127);
            Random X = new Random(System.Environment.TickCount);
            lc = Encoding.ASCII.GetBytes("TCLY");
            pocketNr[0] = (byte)X.Next(0, 255);
            pocketNr[1] = (byte)X.Next(0, 255);
            pocketNr[2] = (byte)X.Next(0, 255);
            pocketNr[3] = (byte)X.Next(0, 255);
            reserv[0] = 0;
            reserv[1] = 0;
            byte[] InstrB1 = new byte[4];
            pocketDl = BitConverter.GetBytes(24);
            Instr = BitConverter.GetBytes(0x00000084);
            InstrB1 = BitConverter.GetBytes(0x00000000);


            byte[] Pocket = new byte[24];

            Pocket[0] = lc[0];
            Pocket[1] = lc[1];
            Pocket[2] = lc[2];
            Pocket[3] = lc[3];
            Pocket[4] = pocketNr[0];
            Pocket[5] = pocketNr[1];
            Pocket[6] = pocketNr[2];
            Pocket[7] = pocketNr[3];
            Pocket[8] = pocketDl[0];
            Pocket[9] = pocketDl[1];
            Pocket[10] = reserv[0];
            Pocket[11] = reserv[1];
            Pocket[12] = Instr[0];
            Pocket[13] = Instr[1];
            Pocket[14] = Instr[2];
            Pocket[15] = Instr[3];
            Pocket[16] = InstrB1[0];
            Pocket[17] = InstrB1[1];
            Pocket[18] = InstrB1[2];
            Pocket[19] = InstrB1[3];
            Pocket[20] = InstrB1[0];
            Pocket[21] = InstrB1[1];
            Pocket[22] = InstrB1[2];
            Pocket[23] = InstrB1[3];
            try
            {
                client.Send(Pocket, Pocket.Length, Cel);
            }
            catch (Exception err)
            {
                MessageBox.Show(err.ToString());
            }   
           finally
            {
                Sodb = " Wysłano ";
                client.Close();
                Wstaw();
            }
        }

        private void button2_Click(object sender, EventArgs e)
        {
            if (nas == false)
            {
                button2.Text = "Rozłącz";
                nas = true;

                Thread odbiornik = new Thread(new ThreadStart(ReciveData));
                odbiornik.IsBackground = true;
                odbiornik.Start();
                Wstaw();
            }
            else
            {
                button2.Text = "Nasłuchuj";
                nas = false;
            }

        }

    }


}