//---------------------------------------------------------------------------
private void ItmCristian_Click(object sender, EventArgs e)
{
try
{
const string ntpServer = "time.windows.com";//default Windows time server
IPAddress[] addresses = Dns.GetHostEntry(ntpServer).AddressList;
//The UDP port number assigned to NTP is 123
IPEndPoint ipEndPoint = new IPEndPoint(addresses[0], 123); //NTP uses UDP
// NTP message size - 16 bytes of the digest (RFC 1305)
byte[] ntpData = new byte[48];
//Setting the Leap Indicator, Version Number and Mode values
ntpData[0] = 0x1B; //LI = 0 (no warning), VN = 3 (IPv4 only), Mode = 3 (Client Mode) 0001
DateTime OriginateSendTimestamp = System.DateTime.Now; //T1
using (Socket socket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp))
{
socket.Connect(ipEndPoint);
socket.ReceiveTimeout = 3000; //Stops code hang if NTP is blocked
socket.Send(ntpData);
socket.Receive(ntpData); // nhan kq tra ve
socket.Close();
}
DateTime OriginateReceiveTimestamp = System.DateTime.Now; //T4
byte Position = 32; //Received Time
DateTime ReceiveTimestamp = DateTimeParser(ntpData, Position).ToLocalTime(); //T2
Position = 40;
DateTime TransmitTimestamp = DateTimeParser(ntpData, Position).ToLocalTime(); //T3
long Theta = (long)Math.Round(((ReceiveTimestamp.Ticks - OriginateSendTimestamp.Ticks) +
(TransmitTimestamp.Ticks - OriginateReceiveTimestamp.Ticks)) / 2.0, 0);
DateTime FinalDateTime = System.DateTime.Now.AddTicks(Theta);
DateTimeUtils.SetDateTime(FinalDateTime.ToUniversalTime());
FinalDateTime = System.DateTime.Now;
TxtLogs.Clear();
string FormatDateTime = "dd/MM/yyyy HH:mm:ss.ms";
TxtLogs.AppendText("Originate Send Timestamp T1: " + OriginateSendTimestamp.ToString(FormatDateTime));
TxtLogs.AppendText(Environment.NewLine);
TxtLogs.AppendText("ReceiveTimestamp T2: " + ReceiveTimestamp.ToString(FormatDateTime));
TxtLogs.AppendText(Environment.NewLine);
TxtLogs.AppendText("Transmit Timestamp T3: " + TransmitTimestamp.ToString(FormatDateTime));
TxtLogs.AppendText(Environment.NewLine);
TxtLogs.AppendText("Originate Receive Time stamp T4: " + OriginateReceiveTimestamp.ToString(FormatDateTime));
TxtLogs.AppendText(Environment.NewLine);
TxtLogs.AppendText("Theta: " + Theta.ToString());
TxtLogs.AppendText(Environment.NewLine);
TxtLogs.AppendText("Final Time: " + FinalDateTime.ToString(FormatDateTime));
}
catch (Exception ex)
{
TxtLogs.AppendText(Environment.NewLine + ex.Message);
}
}
//---------------------------------------------------------------------------
private DateTime DateTimeParser(byte[] ntpData, byte Position)
{
DateTime RetVal = new DateTime(1900, 1, 1, 0, 0, 0, DateTimeKind.Utc);//**UTC** time
try
{
ulong intPart = BitConverter.ToUInt32(ntpData, Position); //Get the seconds part
ulong fractPart = BitConverter.ToUInt32(ntpData, Position + 4); //Get the seconds fraction
//Convert From big-endian to little-endian
intPart = SwapEndianness(intPart);
fractPart = SwapEndianness(fractPart);
ulong milliseconds = (intPart * 1000) + ((fractPart * 1000) / 0x100000000L);
RetVal = RetVal.AddMilliseconds((long)milliseconds);
}
catch (Exception ex)
{
TxtLogs.AppendText(Environment.NewLine + ex.Message);
}
return(RetVal);
}
private void addLog(string text)
{
TxtLogs.AppendText(string.Format("{0}: {1}\n", DateTime.Now.ToString("hh:mm:ss"), text));
TxtLogs.ScrollToEnd();
}
