public static extern bool EnumDisplaySettings(string deviceName, int modeNum, ref DEVMODE devMode);
public bool SwitchPrimaryDisplay(string deviceName)
{
var displays = Enumerate();
var device = displays.Find(d => d.DeviceName.Equals(deviceName));
if (!device.DeviceName.Equals(deviceName))
{
return(false);
}
var deviceMode = new DEVMODE();
if (!EnumDisplaySettings(device.DeviceName, -1, ref deviceMode))
{
return(false);
}
var offsetx = deviceMode.dmPosition.x;
var offsety = deviceMode.dmPosition.y;
if (offsetx == 0 && offsety == 0)
{
return(true);
}
deviceMode.dmPosition.x = 0;
deviceMode.dmPosition.y = 0;
if (ChangeDisplaySettingsEx(
device.DeviceName,
ref deviceMode,
(IntPtr)null,
(ChangeDisplaySettingsFlags.CDS_SET_PRIMARY | ChangeDisplaySettingsFlags.CDS_UPDATEREGISTRY | ChangeDisplaySettingsFlags.CDS_NORESET),
IntPtr.Zero) != DISP_CHANGE.Successful)
{
return(false);
}
var otherDisplays = displays.FindAll(d => !d.DeviceName.Equals(deviceName));
foreach (var otherDisplay in otherDisplays)
{
var otherMode = new DEVMODE();
if (!EnumDisplaySettings(otherDisplay.DeviceName, -1, ref otherMode))
{
return(false);
}
otherMode.dmPosition.x -= offsetx;
otherMode.dmPosition.y -= offsety;
if (ChangeDisplaySettingsEx(
otherDisplay.DeviceName,
ref otherMode,
(IntPtr)null,
(ChangeDisplaySettingsFlags.CDS_UPDATEREGISTRY | ChangeDisplaySettingsFlags.CDS_NORESET),
IntPtr.Zero) != DISP_CHANGE.Successful)
{
return(false);
}
}
return(ChangeDisplaySettingsEx(null, IntPtr.Zero, (IntPtr)null, ChangeDisplaySettingsFlags.CDS_NONE, (IntPtr)null) == DISP_CHANGE.Successful);
}
public static extern DISP_CHANGE ChangeDisplaySettingsEx(string lpszDeviceName, ref DEVMODE lpDevMode, IntPtr hwnd, ChangeDisplaySettingsFlags dwflags, IntPtr lParam);