using System;
using System.Runtime.InteropServices;
using System.Windows.Forms;
 
namespace ConsoleApplication1
{
    partial class Program
    {
        public const int ENUM_CURRENT_SETTINGS = -1;
 
        [StructLayout(LayoutKind.Sequential)]
        public struct DISPLAY_DEVICE
        {
            public int cb;
            [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 32)]
            public string DeviceName;
            [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 128)]
            public string DeviceString;
            public int StateFlags;
            [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 128)]
            public string DeviceID;
            [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 128)]
            public string DeviceKey;
 
            public DISPLAY_DEVICE(int flags)
            {
                cb = 0;
                StateFlags = flags;
                DeviceName = new string((char)32, 32);
                DeviceString = new string((char)32, 128);
                DeviceID = new string((char)32, 128);
                DeviceKey = new string((char)32, 128);
                cb = Marshal.SizeOf(this);
            }
        }
 
        [StructLayout(LayoutKind.Sequential)]
        public struct DEVMODE
        {
            [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 32)]
            public string dmDeviceName;
            public short dmSpecVersion;
            public short dmDriverVersion;
            public short dmSize;
            public short dmDriverExtra;
            public int dmFields;
            public short dmOrientation;
            public short dmPaperSize;
            public short dmPaperLength;
            public short dmPaperWidth;
            public short dmScale;
            public short dmCopies;
            public short dmDefaultSource;
            public short dmPrintQuality;
            public short dmColor;
            public short dmDuplex;
            public short dmYResolution;
            public short dmTTOption;
            public short dmCollate;
            [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 32)]
            public string dmFormName;
            public short dmUnusedPadding;
            public short dmBitsPerPel;
            public int dmPelsWidth;
            public int dmPelsHeight;
            public int dmDisplayFlags;
            public int dmDisplayFrequency;
        }
 
        static void EnumMonitors()
        {
            foreach (Screen screen in Screen.AllScreens)
            {
                Console.WriteLine("*** Managed output");
 
                Console.WriteLine("Display Device: {0}\t\n" +
                    "\tBPP={1}\n\tWidth={2}\n\tHeight={3}\n\n",
                    screen.DeviceName, screen.BitsPerPixel,
                    screen.Bounds.Width, screen.Bounds.Height);
 
                DISPLAY_DEVICE monitor =
                    new DISPLAY_DEVICE(0);
 
                EnumDisplayDevices(screen.DeviceName, 0,
                    ref monitor, 0);
 
                DEVMODE dm = new DEVMODE();
 
                EnumDisplaySettings(screen.DeviceName,
                    ENUM_CURRENT_SETTINGS, ref dm);
 
                Console.WriteLine("*** Unmanaged output");
 
                Console.WriteLine("\tMonitor: {0}\n\t\t{1}\n\t\t{2}",
                    monitor.DeviceName, 
                    monitor.DeviceString, monitor.DeviceID);
 
                Console.WriteLine(
                    "\t\t\tFreq.={0}\n" +
                    "\t\t\tBPP={1}\n" +
                    "\t\t\tWidth={2}\n" +
                    "\t\t\tHeight={3}\n",
                    dm.dmDisplayFrequency, dm.dmBitsPerPel,
                    dm.dmPelsWidth, dm.dmPelsHeight);
 
            }
            Console.WriteLine("Number of monitors: {0}", 
                Screen.AllScreens.Length);
        }
 
        [DllImport("User32.dll")]
        private static extern bool EnumDisplayDevices(
            string lpDevice, int iDevNum,
            ref DISPLAY_DEVICE lpDisplayDevice, int dwFlags);
 
        [DllImport("User32.dll")]
        private static extern bool EnumDisplaySettings(
            string devName, int modeNum, ref DEVMODE devMode);
 
    }
}