How do I get the actual Monitor name? as seen in the resolution dialog

Question

I am trying to grab the friendly name for the monitors on my system. I am using C#.

I have tried Screen, which just gives me //./DisplayXX. I have also tried both Win32_DesktopMonitor and EnumDisplayDevices, they all give me variations of //./DisplayXX OR Generic Monitor, whereas I know my displays names are SyncMaster and SM2333T.

Now Windows knows what these monitors are, displays them in the Devices and Printers windows with the correct names, and also in the dialog for setting location and resolution.

Where can I grab these names from? I have looked in the registry and cant seem to find them, so any help will be great.

SOLUTION: The issue I had was when calling EnumDisplayDevices the second time I was setting iDevNum to id again, which meant I was trying to grab data from the wrong place, I then replaced this with 0, and it works perfectly, see below for the code.

    var device = new DISPLAY_DEVICE();
    device.cb = Marshal.SizeOf(device);
    try
    {
        for (uint id = 0; EnumDisplayDevices(null, id, ref device, 0); id++)
        { 
                Console.WriteLine(String.Format("{0}, {1}, {2}, {3}, {4}, {5}", id, device.DeviceName, device.DeviceString, device.StateFlags, device.DeviceID, device.DeviceKey));
                Console.WriteLine();
                device.cb = Marshal.SizeOf(device);

                EnumDisplayDevices(device.DeviceName, 0, ref device, 0);

                Console.WriteLine(String.Format("{0}, {1}, {2}, {3}, {4}, {5}", id, device.DeviceName, device.DeviceString, device.StateFlags, device.DeviceID, device.DeviceKey));
                device.cb = Marshal.SizeOf(device);

                device.cb = Marshal.SizeOf(device);
                return;
            }

        }
    }
    catch (Exception ex)
    {
        Console.WriteLine(String.Format("{0}", ex.ToString()));
    }

Answer 1

Examine carefully! this is what you looking for, you can now write Screen.PrimaryScreen.DeviceFriendlyName() and get the real name of the monitor device.
(and yes, it is the same name seen in resolution dialog)

While I did add some personal touch to wrap this code I did not create the Hard-Core part of it, And so I would like to thank 2 developers, The MS developer who gave the essentials in C++ and the anonymous developer who translated those essentials to C# code.

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Runtime.InteropServices;
using System.Windows.Forms;
using Tools;

namespace ConsoleApplication35
{
    internal class Program
    {

        private static void Main()
        {

            Console.WriteLine(Screen.PrimaryScreen.DeviceFriendlyName());

            //output: ASUS MK241

            Console.ReadLine();
        }
    }
}

namespace Tools
{
    public static class ScreenInterrogatory
    {
        public const int ERROR_SUCCESS = 0;

        #region enums

        public enum QUERY_DEVICE_CONFIG_FLAGS : uint
        {
            QDC_ALL_PATHS = 0x00000001,
            QDC_ONLY_ACTIVE_PATHS = 0x00000002,
            QDC_DATABASE_CURRENT = 0x00000004
        }

        public enum DISPLAYCONFIG_VIDEO_OUTPUT_TECHNOLOGY : uint
        {
            DISPLAYCONFIG_OUTPUT_TECHNOLOGY_OTHER = 0xFFFFFFFF,
            DISPLAYCONFIG_OUTPUT_TECHNOLOGY_HD15 = 0,
            DISPLAYCONFIG_OUTPUT_TECHNOLOGY_SVIDEO = 1,
            DISPLAYCONFIG_OUTPUT_TECHNOLOGY_COMPOSITE_VIDEO = 2,
            DISPLAYCONFIG_OUTPUT_TECHNOLOGY_COMPONENT_VIDEO = 3,
            DISPLAYCONFIG_OUTPUT_TECHNOLOGY_DVI = 4,
            DISPLAYCONFIG_OUTPUT_TECHNOLOGY_HDMI = 5,
            DISPLAYCONFIG_OUTPUT_TECHNOLOGY_LVDS = 6,
            DISPLAYCONFIG_OUTPUT_TECHNOLOGY_D_JPN = 8,
            DISPLAYCONFIG_OUTPUT_TECHNOLOGY_SDI = 9,
            DISPLAYCONFIG_OUTPUT_TECHNOLOGY_DISPLAYPORT_EXTERNAL = 10,
            DISPLAYCONFIG_OUTPUT_TECHNOLOGY_DISPLAYPORT_EMBEDDED = 11,
            DISPLAYCONFIG_OUTPUT_TECHNOLOGY_UDI_EXTERNAL = 12,
            DISPLAYCONFIG_OUTPUT_TECHNOLOGY_UDI_EMBEDDED = 13,
            DISPLAYCONFIG_OUTPUT_TECHNOLOGY_SDTVDONGLE = 14,
            DISPLAYCONFIG_OUTPUT_TECHNOLOGY_MIRACAST = 15,
            DISPLAYCONFIG_OUTPUT_TECHNOLOGY_INTERNAL = 0x80000000,
            DISPLAYCONFIG_OUTPUT_TECHNOLOGY_FORCE_UINT32 = 0xFFFFFFFF
        }

        public enum DISPLAYCONFIG_SCANLINE_ORDERING : uint
        {
            DISPLAYCONFIG_SCANLINE_ORDERING_UNSPECIFIED = 0,
            DISPLAYCONFIG_SCANLINE_ORDERING_PROGRESSIVE = 1,
            DISPLAYCONFIG_SCANLINE_ORDERING_INTERLACED = 2,
            DISPLAYCONFIG_SCANLINE_ORDERING_INTERLACED_UPPERFIELDFIRST = DISPLAYCONFIG_SCANLINE_ORDERING_INTERLACED,
            DISPLAYCONFIG_SCANLINE_ORDERING_INTERLACED_LOWERFIELDFIRST = 3,
            DISPLAYCONFIG_SCANLINE_ORDERING_FORCE_UINT32 = 0xFFFFFFFF
        }

        public enum DISPLAYCONFIG_ROTATION : uint
        {
            DISPLAYCONFIG_ROTATION_IDENTITY = 1,
            DISPLAYCONFIG_ROTATION_ROTATE90 = 2,
            DISPLAYCONFIG_ROTATION_ROTATE180 = 3,
            DISPLAYCONFIG_ROTATION_ROTATE270 = 4,
            DISPLAYCONFIG_ROTATION_FORCE_UINT32 = 0xFFFFFFFF
        }

        public enum DISPLAYCONFIG_SCALING : uint
        {
            DISPLAYCONFIG_SCALING_IDENTITY = 1,
            DISPLAYCONFIG_SCALING_CENTERED = 2,
            DISPLAYCONFIG_SCALING_STRETCHED = 3,
            DISPLAYCONFIG_SCALING_ASPECTRATIOCENTEREDMAX = 4,
            DISPLAYCONFIG_SCALING_CUSTOM = 5,
            DISPLAYCONFIG_SCALING_PREFERRED = 128,
            DISPLAYCONFIG_SCALING_FORCE_UINT32 = 0xFFFFFFFF
        }

        public enum DISPLAYCONFIG_PIXELFORMAT : uint
        {
            DISPLAYCONFIG_PIXELFORMAT_8BPP = 1,
            DISPLAYCONFIG_PIXELFORMAT_16BPP = 2,
            DISPLAYCONFIG_PIXELFORMAT_24BPP = 3,
            DISPLAYCONFIG_PIXELFORMAT_32BPP = 4,
            DISPLAYCONFIG_PIXELFORMAT_NONGDI = 5,
            DISPLAYCONFIG_PIXELFORMAT_FORCE_UINT32 = 0xffffffff
        }

        public enum DISPLAYCONFIG_MODE_INFO_TYPE : uint
        {
            DISPLAYCONFIG_MODE_INFO_TYPE_SOURCE = 1,
            DISPLAYCONFIG_MODE_INFO_TYPE_TARGET = 2,
            DISPLAYCONFIG_MODE_INFO_TYPE_FORCE_UINT32 = 0xFFFFFFFF
        }

        public enum DISPLAYCONFIG_DEVICE_INFO_TYPE : uint
        {
            DISPLAYCONFIG_DEVICE_INFO_GET_SOURCE_NAME = 1,
            DISPLAYCONFIG_DEVICE_INFO_GET_TARGET_NAME = 2,
            DISPLAYCONFIG_DEVICE_INFO_GET_TARGET_PREFERRED_MODE = 3,
            DISPLAYCONFIG_DEVICE_INFO_GET_ADAPTER_NAME = 4,
            DISPLAYCONFIG_DEVICE_INFO_SET_TARGET_PERSISTENCE = 5,
            DISPLAYCONFIG_DEVICE_INFO_GET_TARGET_BASE_TYPE = 6,
            DISPLAYCONFIG_DEVICE_INFO_FORCE_UINT32 = 0xFFFFFFFF
        }

        #endregion

        #region structs

        [StructLayout(LayoutKind.Sequential)]
        public struct LUID
        {
            public uint LowPart;
            public int HighPart;
        }

        [StructLayout(LayoutKind.Sequential)]
        public struct DISPLAYCONFIG_PATH_SOURCE_INFO
        {
            public LUID adapterId;
            public uint id;
            public uint modeInfoIdx;
            public uint statusFlags;
        }

        [StructLayout(LayoutKind.Sequential)]
        public struct DISPLAYCONFIG_PATH_TARGET_INFO
        {
            public LUID adapterId;
            public uint id;
            public uint modeInfoIdx;
            private DISPLAYCONFIG_VIDEO_OUTPUT_TECHNOLOGY outputTechnology;
            private DISPLAYCONFIG_ROTATION rotation;
            private DISPLAYCONFIG_SCALING scaling;
            private DISPLAYCONFIG_RATIONAL refreshRate;
            private DISPLAYCONFIG_SCANLINE_ORDERING scanLineOrdering;
            public bool targetAvailable;
            public uint statusFlags;
        }

        [StructLayout(LayoutKind.Sequential)]
        public struct DISPLAYCONFIG_RATIONAL
        {
            public uint Numerator;
            public uint Denominator;
        }

        [StructLayout(LayoutKind.Sequential)]
        public struct DISPLAYCONFIG_PATH_INFO
        {
            public DISPLAYCONFIG_PATH_SOURCE_INFO sourceInfo;
            public DISPLAYCONFIG_PATH_TARGET_INFO targetInfo;
            public uint flags;
        }

        [StructLayout(LayoutKind.Sequential)]
        public struct DISPLAYCONFIG_2DREGION
        {
            public uint cx;
            public uint cy;
        }

        [StructLayout(LayoutKind.Sequential)]
        public struct DISPLAYCONFIG_VIDEO_SIGNAL_INFO
        {
            public ulong pixelRate;
            public DISPLAYCONFIG_RATIONAL hSyncFreq;
            public DISPLAYCONFIG_RATIONAL vSyncFreq;
            public DISPLAYCONFIG_2DREGION activeSize;
            public DISPLAYCONFIG_2DREGION totalSize;
            public uint videoStandard;
            public DISPLAYCONFIG_SCANLINE_ORDERING scanLineOrdering;
        }

        [StructLayout(LayoutKind.Sequential)]
        public struct DISPLAYCONFIG_TARGET_MODE
        {
            public DISPLAYCONFIG_VIDEO_SIGNAL_INFO targetVideoSignalInfo;
        }

        [StructLayout(LayoutKind.Sequential)]
        public struct POINTL
        {
            private int x;
            private int y;
        }

        [StructLayout(LayoutKind.Sequential)]
        public struct DISPLAYCONFIG_SOURCE_MODE
        {
            public uint width;
            public uint height;
            public DISPLAYCONFIG_PIXELFORMAT pixelFormat;
            public POINTL position;
        }

        [StructLayout(LayoutKind.Explicit)]
        public struct DISPLAYCONFIG_MODE_INFO_UNION
        {
            [FieldOffset(0)]
            public DISPLAYCONFIG_TARGET_MODE targetMode;

            [FieldOffset(0)]
            public DISPLAYCONFIG_SOURCE_MODE sourceMode;
        }

        [StructLayout(LayoutKind.Sequential)]
        public struct DISPLAYCONFIG_MODE_INFO
        {
            public DISPLAYCONFIG_MODE_INFO_TYPE infoType;
            public uint id;
            public LUID adapterId;
            public DISPLAYCONFIG_MODE_INFO_UNION modeInfo;
        }

        [StructLayout(LayoutKind.Sequential)]
        public struct DISPLAYCONFIG_TARGET_DEVICE_NAME_FLAGS
        {
            public uint value;
        }

        [StructLayout(LayoutKind.Sequential)]
        public struct DISPLAYCONFIG_DEVICE_INFO_HEADER
        {
            public DISPLAYCONFIG_DEVICE_INFO_TYPE type;
            public uint size;
            public LUID adapterId;
            public uint id;
        }

        [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
        public struct DISPLAYCONFIG_TARGET_DEVICE_NAME
        {
            public DISPLAYCONFIG_DEVICE_INFO_HEADER header;
            public DISPLAYCONFIG_TARGET_DEVICE_NAME_FLAGS flags;
            public DISPLAYCONFIG_VIDEO_OUTPUT_TECHNOLOGY outputTechnology;
            public ushort edidManufactureId;
            public ushort edidProductCodeId;
            public uint connectorInstance;

            [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 64)]
            public string monitorFriendlyDeviceName;

            [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 128)]
            public string monitorDevicePath;
        }

        #endregion

        #region DLL-Imports

        [DllImport("user32.dll")]
        public static extern int GetDisplayConfigBufferSizes(
            QUERY_DEVICE_CONFIG_FLAGS flags, out uint numPathArrayElements, out uint numModeInfoArrayElements);

        [DllImport("user32.dll")]
        public static extern int QueryDisplayConfig(
            QUERY_DEVICE_CONFIG_FLAGS flags,
            ref uint numPathArrayElements, [Out] DISPLAYCONFIG_PATH_INFO[] PathInfoArray,
            ref uint numModeInfoArrayElements, [Out] DISPLAYCONFIG_MODE_INFO[] ModeInfoArray,
            IntPtr currentTopologyId
            );

        [DllImport("user32.dll")]
        public static extern int DisplayConfigGetDeviceInfo(ref DISPLAYCONFIG_TARGET_DEVICE_NAME deviceName);

        #endregion

        private static string MonitorFriendlyName(LUID adapterId, uint targetId)
        {
            var deviceName = new DISPLAYCONFIG_TARGET_DEVICE_NAME
            {
                header =
                {
                    size = (uint)Marshal.SizeOf(typeof (DISPLAYCONFIG_TARGET_DEVICE_NAME)),
                    adapterId = adapterId,
                    id = targetId,
                    type = DISPLAYCONFIG_DEVICE_INFO_TYPE.DISPLAYCONFIG_DEVICE_INFO_GET_TARGET_NAME
                }
            };
            var error = DisplayConfigGetDeviceInfo(ref deviceName);
            if (error != ERROR_SUCCESS)
                throw new Win32Exception(error);
            return deviceName.monitorFriendlyDeviceName;
        }

        private static IEnumerable<string> GetAllMonitorsFriendlyNames()
        {
            uint pathCount, modeCount;
            var error = GetDisplayConfigBufferSizes(QUERY_DEVICE_CONFIG_FLAGS.QDC_ONLY_ACTIVE_PATHS, out pathCount, out modeCount);
            if (error != ERROR_SUCCESS)
                throw new Win32Exception(error);

            var displayPaths = new DISPLAYCONFIG_PATH_INFO[pathCount];
            var displayModes = new DISPLAYCONFIG_MODE_INFO[modeCount];
            error = QueryDisplayConfig(QUERY_DEVICE_CONFIG_FLAGS.QDC_ONLY_ACTIVE_PATHS,
                ref pathCount, displayPaths, ref modeCount, displayModes, IntPtr.Zero);
            if (error != ERROR_SUCCESS)
                throw new Win32Exception(error);

            for (var i = 0; i < modeCount; i++)
                if (displayModes[i].infoType == DISPLAYCONFIG_MODE_INFO_TYPE.DISPLAYCONFIG_MODE_INFO_TYPE_TARGET)
                    yield return MonitorFriendlyName(displayModes[i].adapterId, displayModes[i].id);
        }

        public static string DeviceFriendlyName(this Screen screen)
        {
            var allFriendlyNames = GetAllMonitorsFriendlyNames();
            for (var index = 0; index < Screen.AllScreens.Length; index++)
                if (Equals(screen, Screen.AllScreens[index]))
                    return allFriendlyNames.ToArray()[index];
            return null;
        }

    }

}

Answer 2

After you get a DisplayDevice.DeviceName like //./DisplayX from EnumDisplayDevices, you are supposed to call 'EnumDisplayDevices' a second time, this time providing the 'DisplayDevice.DeviceName' that you got from the previous call as lpDevice, and '0' as iDevNum. Then you'll have the monitor name in DisplayDevice.DeviceString.

Answer 3

This information is almost certainly obtained through the SetupAPI family of functions. I don't recall the specifics off the top of my head, but you will need to get all monitor devices (GUID_DEVINTERFACE_MONITOR) and obtain their friendly names (SPDRP_FRIENDLYNAME).