以编程方式更改屏幕方向(3)

// initialize the DEVMODE structure

DEVMODE dm = new DEVMODE();

dm.dmDeviceName = new string(new char[32]);

dm.dmFormName = new string(new char[32]);

dm.dmSize = Marshal.SizeOf(dm);
if (0 != NativeMethods.EnumDisplaySettings(

null,

NativeMethods.ENUM_CURRENT_SETTINGS,

ref dm))

{

// swap width and height

int temp = dm.dmPelsHeight;

dm.dmPelsHeight = dm.dmPelsWidth;

dm.dmPelsWidth = temp;
// determine new orientation

switch(dm.dmDisplayOrientation)

{

case NativeMethods.DMDO_DEFAULT:

dm.dmDisplayOrientation = NativeMethods.DMDO_270;

break;

case NativeMethods.DMDO_270:

dm.dmDisplayOrientation = NativeMethods.DMDO_180;

break;

case NativeMethods.DMDO_180:

dm.dmDisplayOrientation = NativeMethods.DMDO_90;

break;

case NativeMethods.DMDO_90:

dm.dmDisplayOrientation = NativeMethods.DMDO_DEFAULT;

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

}

}