Windows操作系统多久才能从唤醒计时器中唤醒

Question

我正在使用C++和Win API编写一个程序。我使用SetSuspendState（）API将系统发送到睡眠模式（有可能在唤醒计时器上唤醒，"DisableWakeEvent"设置为FALSE。）然后，我使用CreateWaitableTimer和SetWaitableTimer API设置实际计时器。问题是，如果我在系统进入睡眠模式后过早设置唤醒计时器，有时系统不会唤醒。

所以我很好奇，从系统进入睡眠模式以来，是否需要经过最短的时间才能用唤醒计时器以编程方式唤醒它？

Answer 1

现在。您的电脑可以使用计时器唤醒：

安排机器唤醒

C#文章如果你不介意：http://www.codeproject.com/Articles/49798/Wake-the-PC-from-standby-or-hibernation

using System;
using System.Text;
using System.Runtime.InteropServices;
using Microsoft.Win32.SafeHandles;
using System.ComponentModel;
using System.Threading;
namespace WakeUPTimer
{
    class WakeUP
    {
        [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 WakeUP()
        {
            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());
                }
            }
        }
    }
}

或者从控制面板：http://www.anuko.com/content/world_clock/faq/enable_wake_timers.htm