C# kommunikation - Arduino

using System;
using System.Text;
using System.Net;
using System.Net.Sockets;

namespace FSPanel_App___Backend
{
    class ConnectionArduinoD1
    {
        public void EthernetStart()
        {
            //InitializeComponent();

            Socket EthernetConnection = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
            IPAddress serverAddress = IPAddress.Parse("192.168.0.166");
            IPEndPoint endPoint = new IPEndPoint(serverAddress, 4000);
            String text = "Hello";
            byte[] send_buffer = Encoding.ASCII.GetBytes(text);

            EthernetConnection.SendTo(send_buffer, endPoint);
            byte[] received_byte = new byte[1024];
            int bytesrec = EthernetConnection.Receive(received_byte);

            Encoding.UTF8.GetString(received_byte, 0, bytesrec);
        }
    }
}