public List <IntPtr> GetAllHMonitorHandles()
 {
     HMONITORS    = new List <IntPtr>();
     enumCallback = new lpfnEnumProc(EnumCallbackHandler);
     EnumDisplayMonitors(IntPtr.Zero, IntPtr.Zero, enumCallback, 0);
     return(HMONITORS);
 }
 public static extern bool EnumDisplayMonitors(IntPtr hdc, IntPtr lprcClip, lpfnEnumProc lpfnEnum, uint dwData);