private void button1_Click(object sender, EventArgs e)
{
// SendMessage( this.Handle.ToInt32() , WM_SYSCOMMAND , SC_MONITORPOWER ,2 );//DLL function //go to powersave.
DISPLAY_DEVICE d = new DISPLAY_DEVICE();
d.cb = Marshal.SizeOf(d);
try
{
for (uint id = 0; EnumDisplayDevices(null, id, ref d, 0); id++)
{
MessageBox.Show(
String.Format("{0}, {1}, {2}, {3}, {4}, {5}",
id,
d.DeviceName,
d.DeviceString,
d.StateFlags,
d.DeviceID,
d.DeviceKey
)
);
d.cb = Marshal.SizeOf(d);
}
}
catch (Exception ex)
{
Console.WriteLine(String.Format("{0}", ex.ToString()));
}
GetDisplayInfo();
ddInactive.dmPosition.x = 0;
ddInactive.dmPosition.y = 0;
ddInactive.dmFields = DM.Position;
if (DISP_CHANGE.Successful == ChangeDisplaySettingsEx(szInactiveDeviceName,
ref ddInactive, IntPtr.Zero,
(int)(CDSFlags.CDS_RESET | CDSFlags.CDS_UPDATEREGISTRY |
CDSFlags.CDS_SET_PRIMARY), IntPtr.Zero))
{
ddActive.dmPosition.x = 0;
ddActive.dmPosition.y = 0;
ddActive.dmPelsHeight = 0;
ddActive.dmPelsWidth = 0;
ddActive.dmFields = DM.PelsHeight | DM.PelsWidth | DM.Position;
ChangeDisplaySettingsEx(szActiveDeviceName, ref ddActive,
IntPtr.Zero, (int)(CDSFlags.CDS_RESET |
CDSFlags.CDS_UPDATEREGISTRY), IntPtr.Zero);
}
}
public void GetDisplayInfo()
{
ddActive.dmSize = (short)Marshal.SizeOf(ddActive);
ddInactive.dmSize = (short)Marshal.SizeOf(ddInactive);
uint iDeviceCntr = 0;
DISPLAY_DEVICE dd = new DISPLAY_DEVICE();
dd.cb = Marshal.SizeOf(dd);
while (EnumDisplayDevices(null, iDeviceCntr, ref dd, 0))
{
DEVMODE dMode = new DEVMODE();
dMode.dmSize = (short)Marshal.SizeOf(dMode);
if (EnumDisplaySettings(dd.DeviceName, ENUM_REGISTRY_SETTINGS, ref dMode))
{
if (dMode.dmPelsHeight > 0 && dMode.dmPelsWidth > 0)
{
if ((dd.StateFlags & DisplayDeviceStateFlags.PrimaryDevice) ==
DisplayDeviceStateFlags.PrimaryDevice)
{
ddActive = dMode;
szActiveDeviceName = dd.DeviceName;
}
else
{
ddInactive = dMode;
szInactiveDeviceName = dd.DeviceName;
}
}
}
iDeviceCntr++;
}
}
static extern bool EnumDisplayDevices(string lpDevice,
uint iDevNum, ref DISPLAY_DEVICE lpDisplayDevice, uint dwFlags);
static extern bool EnumDisplayDevices(string lpDevice,
uint iDevNum, ref DISPLAY_DEVICE lpDisplayDevice, uint dwFlags);
