The following code example (from here) creates a waitable timer and set the system in hibernation mode. After resuming back I expected an event with executable code:
class WakeUpTimer
{
[DllImport("kernel32.dll")]
public static extern SafeWaitHandle CreateWaitableTimer(IntPtr lpTimerAttributes,
bool bManualReset,
string lpTimerName);
[DllImport("kernel32.dll", SetLastError = true)]
[return: MarshalAs(UnmanagedType.Bool)]
public static extern bool SetWaitableTimer(SafeWaitHandle hTimer,
[In] ref long pDueTime,
int lPeriod,
IntPtr pfnCompletionRoutine,
IntPtr lpArgToCompletionRoutine,
bool fResume);
public event EventHandler Woken;
private BackgroundWorker bgWorker = new BackgroundWorker();
public WakeUpTimer()
{
bgWorker.DoWork += new DoWorkEventHandler(bgWorker_DoWork);
bgWorker.RunWorkerCompleted += new RunWorkerCompletedEventHandler(bgWorker_RunWorkerCompleted);
}
public void SetWakeUpTime(DateTime time)
{
bgWorker.RunWorkerAsync(time.ToFileTime());
}
void bgWorker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
if (Woken != null)
{
Woken(this, new EventArgs());
}
}
private void bgWorker_DoWork(object sender, DoWorkEventArgs e)
{
long waketime = (long)e.Argument;
using (SafeWaitHandle handle = CreateWaitableTimer(IntPtr.Zero, true, this.GetType().Assembly.GetName().Name.ToString() + "Timer"))
{
if (SetWaitableTimer(handle, ref waketime, 0, IntPtr.Zero, IntPtr.Zero, true))
{
using (EventWaitHandle wh = new EventWaitHandle(false, EventResetMode.AutoReset))
{
wh.SafeWaitHandle = handle;
wh.WaitOne();
}
}
else
{
throw new Win32Exception(Marshal.GetLastWin32Error());
}
}
}
}
Usage of this class is as follows:
private void setHibernation(DateTime dateTime)
{
WakeUpTimer wakeUpTimer = new WakeUpTimer();
wakeUpTimer.Woken += backFromHibernate;
wakeUpTimer.SetWakeUpTime(dateTime);
Application.SetSuspendState(PowerState.Hibernate, false, false);
Debug.WriteLine("---Hibernation starts at " + DateTime.Now + " ---");
}
private void backFromHibernate(object sender, EventArgs e)
{
Debug.WriteLine("I execute this now " + DateTime.Now);
}
As I tested before this scenario several times, the code in the method backFromHibernation is executed immediately (1 sec after setSupsendState duo to debug logs).
Am I wrong or should the method be called when the system is back up from hibernation?
Would appriciate some help, would need such an event - fired automatically after wake up.
EDIT: Set hibernation for 2 min, all works great system comes up automatically.