Setting system date and time from the application

Question

I have a application that is developed using .Net Compact frame work 3.5, i need to synchronize the device date and time with the central server on every web service call.

Thanks.

Answer 1

If you have the NTP client on your device, you can use that. The server(s) are configured in a multistring registry value at:

[HKLM\Services\TIMESVC]
server

Here is code how to force the client to sync. Otherwise there is a registry value for how often the client syncs (DWORD for ms):

[HKLM\Services\TIMESVC]
Refresh

Force sync:

internal static class NativeMethods
{
    internal const int INVALID_HANDLE_VALUE = -1;
    internal const int IOCTL_SERVICE_CONTROL = (0x104 << 16) | (7 << 2);
    internal const uint GENERIC_READ = 0x80000000;
    internal const uint GENERIC_WRITE = 0x40000000;
    internal const int OPEN_EXISTING = 3;

    [DllImport("coredll.dll", SetLastError = true)]
    internal static extern IntPtr CreateFile(
        string lpFileName, 
        uint dwDesiredAccess, 
        uint dwShareMode, 
        IntPtr lpSecurityAttributes, 
        uint dwCreationDisposition, 
        uint dwFlagsAndAttributes, 
        IntPtr hTemplateFile);

    [DllImport("coredll.dll", SetLastError = true)]
    [return: MarshalAs(UnmanagedType.Bool)]
    internal static extern bool DeviceIoControl(
        IntPtr hDevice,
        int dwIoControlCode,
        byte[] lpInBuffer,
        int nInBufferSize,
        byte[] lpOutBuffer,
        int nOutBufferSize,
        ref int lpBytesReturned,
        IntPtr lpOverlapped);

    [DllImport("coredll.dll", SetLastError = true)]
    [return: MarshalAs(UnmanagedType.Bool)]
    internal static extern bool CloseHandle(IntPtr hObject);
}

internal static class TimeServer
{
    public static bool SyncTime()
    {
        byte[] input = System.Text.Encoding.Unicode.GetBytes("Sync\0");
        return TimeServer.DeviceIOCTL("NTP0:", NativeMethods.IOCTL_SERVICE_CONTROL, input);
    }

    private static bool DeviceIOCTL(string deviceName, int ioctl, byte[] input)
    {
        int size = 0;
        return TimeServer.DeviceIOCTL(deviceName, ioctl, input, null, ref size);
    }

    public static bool DeviceIOCTL(string deviceName, int ioctl, byte[] input, byte[] output, ref int bytesReceived)
    {
        bool result = false;

        IntPtr deviceHandle = NativeMethods.CreateFile(
            deviceName, 
            NativeMethods.GENERIC_READ | NativeMethods.GENERIC_WRITE, 
            0, 
            IntPtr.Zero, 
            (uint)NativeMethods.OPEN_EXISTING, 
            0, 
            IntPtr.Zero);

        if (deviceHandle.ToInt32() != NativeMethods.INVALID_HANDLE_VALUE)
        {
            try
            {
                result = NativeMethods.DeviceIoControl(
                    deviceHandle,
                    ioctl,
                    input,
                    (input == null) ? 0 : input.Length,
                    output,
                    (output == null) ? 0 : output.Length,
                    ref bytesReceived,
                    IntPtr.Zero);
            }
            finally
            {
                NativeMethods.CloseHandle(deviceHandle);
            }
        }

        return result;
    }
}