c# How to get the events when the screen/display goes to power OFF or ON?

Question

Hi I have been searching but I can\'t find the answer. How do I know when the screen is going off or on. Not the SystemEvents.PowerModeChanged . I dont know how to retrieve

Answer 1

The missing part was that I didn't register for the events.

Found that there's a power management example from Microsoft:

http://www.microsoft.com/en-us/download/details.aspx?id=4234

hMonitorOn = RegisterPowerSettingNotification(this.Handle,ref GUID_MONITOR_POWER_ON,DEVICE_NOTIFY_WINDOW_HANDLE);

[DllImport("User32", SetLastError = true,EntryPoint = "RegisterPowerSettingNotification",CallingConvention = CallingConvention.StdCall)]
private static extern IntPtr RegisterPowerSettingNotification(IntPtr hRecipient,ref Guid PowerSettingGuid,Int32 Flags);

[DllImport("User32", EntryPoint = "UnregisterPowerSettingNotification",CallingConvention = CallingConvention.StdCall)]
private static extern bool UnregisterPowerSettingNotification(IntPtr handle);

// This structure is sent when the PBT_POWERSETTINGSCHANGE message is sent.
// It describes the power setting that has changed and contains data about the change
[StructLayout(LayoutKind.Sequential, Pack = 4)]
internal struct POWERBROADCAST_SETTING
{
    public Guid PowerSetting;
    public Int32 DataLength;
}