#3
copilot 寫的

// TCP Server
TcpListener listener = new TcpListener(IPAddress.Parse("192.168.1.1"), 61250);
listener.Start();
TcpClient client = listener.AcceptTcpClient();
NetworkStream stream = client.GetStream();
byte[] buffer = new byte[1024];
int bytesRead = stream.Read(buffer, 0, buffer.Length);
File.WriteAllBytes("received_file", buffer);
stream.Close();
client.Close();
listener.Stop();

// TCP Client
TcpClient client = new TcpClient("192.168.1.1", 61250);
NetworkStream stream = client.GetStream();
byte[] fileBytes = File.ReadAllBytes("file_to_send");
stream.Write(fileBytes, 0, fileBytes.Length);
stream.Close();
client.Close();

// UDP Checksum
UdpClient udpClient = new UdpClient();
udpClient.Connect("192.168.1.1", 61250);
byte[] crcData = CalculateCRC(fileBytes);
udpClient.Send(crcData, crcData.Length);

// MAC Address
foreach (NetworkInterface nic in NetworkInterface.GetAllNetworkInterfaces())
{
if (nic.OperationalStatus == OperationalStatus.Up)
{
Console.WriteLine(nic.GetPhysicalAddress().ToString());
}
}