/// <summary>
/// 从配置信息中获取远程时间服务器的设置
/// </summary>
/// <returns></returns>
public static RemoteSNTPServer GetSNTPServer()
{
SNTPSettings settings = SNTPSettings.GetConfig();
RemoteSNTPServer server = RemoteSNTPServer.Default;
if (settings != null)
{
server = new RemoteSNTPServer(settings.ServerName, settings.Port);
}
return(server);
}
/// <summary>
/// This is the 'nuts and bolts' method that queries the server.
/// </summary>
/// <returns>A QueryServerResults instance that holds the results of the query.</returns>
private QueryServerCompletedEventArgs QueryServer()
{
QueryServerCompletedEventArgs result = new QueryServerCompletedEventArgs();
Initialize();
using (UdpClient client = new UdpClient())
{
try
{
// Configure and connect the socket.
IPEndPoint ipEndPoint = RemoteSNTPServer.GetIPEndPoint();
client.Client.SendTimeout = (int)this.Timeout.TotalMilliseconds;
client.Client.ReceiveTimeout = (int)this.Timeout.TotalMilliseconds;
client.Connect(ipEndPoint);
// Send and receive the data, and save the completion DateTime.
SNTPData request = SNTPData.GetClientRequestPacket(this.VersionNumber);
client.Send(request, request.Length);
result.Data = client.Receive(ref ipEndPoint);
result.Data.DestinationDateTime = DateTime.Now.ToUniversalTime();
// Check the data
if (result.Data.Mode == Mode.Server)
{
result.Succeeded = true;
// Call other method(s) if needed
if (this.UpdateLocalDateTime)
{
this.UpdateTime(result.Data.LocalClockOffset);
result.LocalDateTimeUpdated = true;
}
}
else
{
result.ErrorData = new ErrorData("The response from the server was invalid.");
}
return(result);
}
catch (Exception ex)
{
result.ErrorData = new ErrorData(ex);
return(result);
}
}
}
/// <summary>
///
/// </summary>
/// <param name="remoteSNTPServer">The server to use.</param>
/// <param name="timeout">The timeout in milliseconds used for sending and receiving.</param>
/// <returns>The real local offset by seconds.</returns>
public static double GetLocalClockOffset(RemoteSNTPServer remoteSNTPServer, TimeSpan timeout)
{
SNTPClient sntpClient = new SNTPClient();
sntpClient.UpdateLocalDateTime = false;
sntpClient.RemoteSNTPServer = remoteSNTPServer;
sntpClient.Timeout = timeout;
QueryServerCompletedEventArgs args = sntpClient.QueryServer();
if (args.Succeeded)
{
return(args.Data.LocalClockOffset);
}
else
{
throw new ApplicationException(args.ErrorData.ErrorText);
}
}
/// <summary>
/// Gets the real local date and time using the default server and the specified timeout.
/// If there is an error or exception, DateTime.MinValue is returned.
/// </summary>
/// <param name="remoteSNTPServer">The server to use.</param>
/// <param name="timeout">The timeout in milliseconds used for sending and receiving.</param>
/// <returns>The real local date and time.</returns>
public static DateTime GetNow(RemoteSNTPServer remoteSNTPServer, TimeSpan timeout)
{
SNTPClient sntpClient = new SNTPClient();
sntpClient.UpdateLocalDateTime = false;
sntpClient.RemoteSNTPServer = remoteSNTPServer;
sntpClient.Timeout = timeout;
QueryServerCompletedEventArgs args = sntpClient.QueryServer();
if (args.Succeeded)
{
return(DateTime.Now.AddSeconds(args.Data.LocalClockOffset));
}
else
{
return(DateTime.MinValue);
}
}
/// <summary>
/// Gets the real local date and time using the specified server and a total timeout of 1 second.
/// If there is an error or exception, DateTime.MinValue is returned.
/// </summary>
/// <param name="remoteSNTPServer">The server to use.</param>
/// <returns>The real local date and time.</returns>
public static DateTime GetNow(RemoteSNTPServer remoteSNTPServer)
{
return(GetNow(remoteSNTPServer, SNTPSettings.GetConfigOrDefault().Timeout));
}