// helper for creating an initialized DEVMODE structure
public static DEVMODE CreateDevmode()
{
DEVMODE dm = new DEVMODE();
dm.dmDeviceName = new String(new char[32]);
dm.dmFormName = new String(new char[32]);
dm.dmSize = (short)Marshal.SizeOf(dm);
return dm;
}
public void PostData(int id, int data)
{
// initialize the DEVMODE structure
DEVMODE dm = new DEVMODE();
dm.dmDeviceName = new string(new char[32]);
dm.dmFormName = new string(new char[32]);
dm.dmSize = (short)Marshal.SizeOf(dm);
if (0 != NativeMethods.EnumDisplaySettings(null, NativeMethods.ENUM_CURRENT_SETTINGS, ref dm))
{
if (data != last_data)
{
// swap width and height
int temp = dm.dmPelsHeight;
dm.dmPelsHeight = dm.dmPelsWidth;
dm.dmPelsWidth = temp;
// determine new orientation
switch (data)
{
case 3:
dm.dmDisplayOrientation = NativeMethods.DMDO_270;
last_data = data;
break;
case 2:
dm.dmDisplayOrientation = NativeMethods.DMDO_180;
last_data = data;
break;
case 1:
dm.dmDisplayOrientation = NativeMethods.DMDO_90;
last_data = data;
break;
case 0:
dm.dmDisplayOrientation = NativeMethods.DMDO_DEFAULT;
last_data = data;
break;
default:
// unknown orientation value
// add exception handling here
break;
}
int iRet = NativeMethods.ChangeDisplaySettings(ref dm, 0);
if (NativeMethods.DISP_CHANGE_SUCCESSFUL != iRet)
{
// add exception handling here
}
}
}
}
public static extern int ChangeDisplaySettings(ref DEVMODE lpDevMode, int dwFlags);
public static extern int EnumDisplaySettings(string lpszDeviceName, int iModeNum, ref DEVMODE lpDevMode);
