// This enumerates all turned on, physical monitors in the system and returns them
// Will return an empty list if none found or on fail
public static IList<MonitorDisplayArea> EnumerateDisplayAreas()
{
// first, iterate over all display devices and find the physical monitor device for each display device (if there is one)
var monitors = new List<MonitorDisplayArea>();
uint numDevicesEnumerated = 0;
var device = new DisplayDevice();
device.Init();
while(DisplayEnumerationAreaExterns.EnumDisplayDevices(null, numDevicesEnumerated, ref device, 0))
{
numDevicesEnumerated++;
uint numMonitorsEnumerated = 0;
var displayMonitor = new DisplayDevice();
displayMonitor.Init();
while(DisplayEnumerationAreaExterns.EnumDisplayDevices(device.DeviceName, numMonitorsEnumerated, ref displayMonitor, 0))
{
numMonitorsEnumerated++;
if((displayMonitor.StateFlags & DisplayDeviceStateFlags.Active) == 0 || (displayMonitor.StateFlags & DisplayDeviceStateFlags.MirroringDriver) != 0)
{
// this monitor is not turned on, or it is not an actual physical monitor
continue;
}
var displayMonitorInterface = new DisplayDevice();
displayMonitorInterface.Init();
if(!DisplayEnumerationAreaExterns.EnumDisplayDevices(device.DeviceName, numMonitorsEnumerated-1, ref displayMonitorInterface, EnumDisplayDevicesFlags.GetDeviceInterfaceName))
{
return new List<MonitorDisplayArea>(); // something broke
}
// store the relevant monitor information we have in the output struct and add to list
var displayArea = new MonitorDisplayArea();
displayArea.displayDeviceName = device.DeviceName;
int start = displayMonitorInterface.DeviceID.IndexOf("DISPLAY");
int stop = displayMonitorInterface.DeviceID.IndexOf('{');
if(start == -1 || stop == -1) return new List<MonitorDisplayArea>();
displayArea.monitorId = displayMonitorInterface.DeviceID.Substring(start, stop - start - 1).Replace("#", "\\").ToUpperInvariant();
monitors.Add(displayArea);
break; // this is correct if there is really only one physical monitor per display device
}
}
// get the virtual desktop bounds of each monitor
DisplayEnumerationAreaExterns.EnumDisplayMonitors(IntPtr.Zero, IntPtr.Zero,
(IntPtr hMonitor, IntPtr hdcMonitor, ref Rect lprcMonitor, IntPtr dwData) =>
{
var monitorInfo = new MonitorInfoEx();
monitorInfo.Init();
if(DisplayEnumerationAreaExterns.GetMonitorInfo(hMonitor, ref monitorInfo))
{
var monitor = monitors.SingleOrDefault(mda => mda.displayDeviceName.Equals(monitorInfo.szDevice));
if(monitor != null)
{
monitor.xVirtual = monitorInfo.rcMonitor.Left;
monitor.yVirtual = monitorInfo.rcMonitor.Top;
monitor.wVirtual = monitorInfo.rcMonitor.Right - monitorInfo.rcMonitor.Left;
monitor.hVirtual = monitorInfo.rcMonitor.Bottom - monitorInfo.rcMonitor.Top;
}
}
return true;
}
, IntPtr.Zero);
return monitors;
}
public static extern bool EnumDisplayDevices(string lpDevice, uint iDevNum, ref DisplayDevice lpDisplayDevice, EnumDisplayDevicesFlags dwFlags);
