I am implementing a system lock by date, and I need to get the current date of brasilia for example, which would be the official time in Brazil, or the date in time zone -3.
I believe there are web services that do this and that are reliable, or maybe even the government provides this type of service.
But I did not find anything that would serve me effectively. So I'm turning to you.
Note: This is a Desktop application and I can not trust the date of the machine running or the database server.
In Delphi if you have installed the components of Indy (in recent versions of Delphi Indy is already built-in ), you can get the time using the IdSntp component.
Example:
{
Na seção "Uses" coloque as units:
IdComponent, IdTCPConnection, IdTCPClient, IdSNTP,
IdBaseComponent, IdUDPClient, IdUDPBase
}
Function ReturnTimeInternet(const Servidor: string): string;
Var
SNTP: TIdSNTP;
begin
SNTP := TIdSNTP.Create(nil);
try
SNTP.Host := Servidor;
Result := TimeToStr(SNTP.DateTime);
finally
SNTP.Disconnect;
SNTP.Free;
end;
end;
Example usage:
procedure TForm1.Button1Click(Sender: TObject);
Var
Tempstr: string;
begin
Tempstr := ReturnTimeInternet('pool.ntp.br'); // Ou um servidor de sua preferência
showmessage(format('O horário atual é %s.',[tempstr]));
end;
Original: link
public static DateTime GetNetworkTime()
{
//Servidor nacional para melhor latência
const string ntpServer = "a.ntp.br";
// Tamanho da mensagem NTP - 16 bytes (RFC 2030)
var ntpData = new byte[48];
//Indicador de Leap (ver RFC), Versão e Modo
ntpData[0] = 0x1B; //LI = 0 (sem warnings), VN = 3 (IPv4 apenas), Mode = 3 (modo cliente)
var addresses = Dns.GetHostEntry(ntpServer).AddressList;
//123 é a porta padrão do NTP
var ipEndPoint = new IPEndPoint(addresses[0], 123);
//NTP usa UDP
var socket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
socket.Connect(ipEndPoint);
//Caso NTP esteja bloqueado, ao menos nao trava o app
socket.ReceiveTimeout = 3000;
socket.Send(ntpData);
socket.Receive(ntpData);
socket.Close();
//Offset para chegar no campo "Transmit Timestamp" (que é
//o do momento da saída do servidor, em formato 64-bit timestamp
const byte serverReplyTime = 40;
//Pegando os segundos
ulong intPart = BitConverter.ToUInt32(ntpData, serverReplyTime);
//e a fração de segundos
ulong fractPart = BitConverter.ToUInt32(ntpData, serverReplyTime + 4);
//Passando de big-endian pra little-endian
intPart = SwapEndianness(intPart);
fractPart = SwapEndianness(fractPart);
var milliseconds = (intPart * 1000) + ((fractPart * 1000) / 0x100000000L);
//Tempo em **UTC**
var networkDateTime = (new DateTime(1900, 1, 1, 0, 0, 0, DateTimeKind.Utc)).AddMilliseconds((long)milliseconds);
return networkDateTime.ToLocalTime();
}
// stackoverflow.com/a/3294698/162671
static uint SwapEndianness(ulong x)
{
return (uint) (((x & 0x000000ff) << 24) +
((x & 0x0000ff00) << 8) +
((x & 0x00ff0000) >> 8) +
((x & 0xff000000) >> 24));
}