Как изменить разрешение экрана? - C#

    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using System.Windows;
    using System.Runtime.InteropServices;
    using System.ComponentModel;
 
namespace LibraryCMS
{
    public static class ScreenAPI
    {
        [DllImport("user32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
        [return: MarshalAs(UnmanagedType.Bool)]
        static extern bool EnumDisplayDevices(
            [In]  string lpszDeviceName,
            [In]  uint iDevNum,
            [In][Out] ref DISPLAY_DEVICE lpDisplayDevice,
            [In]  uint dwFlags);
 
        [DllImport("user32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
        [return: MarshalAs(UnmanagedType.Bool)]
        static extern bool EnumDisplaySettingsExW(
            [In]  string lpszDeviceName,
            [In]  uint iModeNum,
            [Out] out DEVMODE lpDevMode,
            [In]  uint dwFlags);
 
        [DllImport("user32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
        static extern int ChangeDisplaySettingsExW(
            [In] string lpszDeviceName,
            [In] ref DEVMODE lpDevMode,
            IntPtr hwnd,
            [In]  uint dwflags,
            [In]  IntPtr lParam);
 
        [DllImport("gdi32.dll", ExactSpelling = true, PreserveSig = true, SetLastError = true)]
        static extern IntPtr SelectObject(IntPtr hdc, IntPtr hgdiobj);
 
        [DllImport("gdi32.dll")]
        static extern IntPtr CreateCompatibleBitmap(IntPtr hdc, int nWidth, int nHeight);
 
        [DllImport("gdi32.dll", SetLastError = true)]
        static extern IntPtr CreateCompatibleDC(IntPtr hdc);
 
        [DllImport("gdi32.dll")]
        static extern bool DeleteObject(IntPtr hObject);
 
        [DllImport("gdi32.dll")]
        static extern IntPtr CreateBitmap(int nWidth, int nHeight, uint cPlanes, uint cBitsPerPel, IntPtr lpvBits);
 
        [DllImport("user32.dll")]
        static extern IntPtr GetDC(IntPtr hWnd);
 
        [DllImport("user32.dll")]
        static extern int ReleaseDC(IntPtr hWnd, IntPtr hDC);
 
        [DllImport("gdi32.dll")]
        static extern bool BitBlt(IntPtr hdc, int nXDest, int nYDest, int nWidth, int nHeight, IntPtr hdcSrc, int nXSrc, int nYSrc, TernaryRasterOperations dwRop);
 
        [StructLayout(LayoutKind.Sequential, Pack = 1, CharSet = CharSet.Unicode)]
        public struct DISPLAY_DEVICE
        {
            public uint cb;
            [MarshalAs(UnmanagedType.ByValArray, SizeConst = 32)]
            public char[] DeviceName;
            [MarshalAs(UnmanagedType.ByValArray, SizeConst = 128)]
            public char[] DeviceString;
            public int StateFlags;
            [MarshalAs(UnmanagedType.ByValArray, SizeConst = 128)]
            public char[] DeviceID;
            [MarshalAs(UnmanagedType.ByValArray, SizeConst = 128)]
            public char[] DeviceKey;
        }
 
        // for ChangeDisplaySettingsEx:
        const uint CDS_UPDATEREGISTRY = 0x1;
        const uint CDS_RESET = 0x40000000;
        // for EnumDisplaySettingsEx:
        const uint ENUM_CURRENT_SETTINGS = uint.MaxValue;
        const uint ENUM_REGISTRY_SETTINGS = uint.MaxValue - 1;
 
        public enum DM_ : uint
        {
            SPECVERSION = 0x0401,
            ORIENTATION = 0x00000001,
            PAPERSIZE = 0x00000002,
            PAPERLENGTH = 0x00000004,
            PAPERWIDTH = 0x00000008,
            SCALE = 0x00000010,
            POSITION = 0x00000020,
            NUP = 0x00000040,
            DISPLAYORIENTATION = 0x00000080,
            COPIES = 0x00000100,
            DEFAULTSOURCE = 0x00000200,
            PRINTQUALITY = 0x00000400,
            COLOR = 0x00000800,
            DUPLEX = 0x00001000,
            YRESOLUTION = 0x00002000,
            TTOPTION = 0x00004000,
            COLLATE = 0x00008000,
            FORMNAME = 0x00010000,
            LOGPIXELS = 0x00020000,
            BITSPERPEL = 0x00040000,
            PELSWIDTH = 0x00080000,
            PELSHEIGHT = 0x00100000,
            DISPLAYFLAGS = 0x00200000,
            DISPLAYFREQUENCY = 0x00400000,
            ICMMETHOD = 0x00800000,
            ICMINTENT = 0x01000000,
            MEDIATYPE = 0x02000000,
            DITHERTYPE = 0x04000000,
            PANNINGWIDTH = 0x08000000,
            PANNINGHEIGHT = 0x10000000,
            DISPLAYFIXEDOUTPUT = 0x20000000
        }
 
        [StructLayout(LayoutKind.Explicit, Pack = 1, Size = 220)]
        public struct DEVMODE
        {
            [FieldOffset(68)]
            public ushort dmSize;
            [FieldOffset(72)]
            public DM_ dmFields;
            [FieldOffset(76)]
            public POINTL dmPosition;
            [FieldOffset(84)]
            public uint dmDisplayOrientation;
            [FieldOffset(168)]
            public uint dmBitsPerPel;
            [FieldOffset(172)]
            public uint dmPelsWidth;
            [FieldOffset(176)]
            public uint dmPelsHeight;
            [FieldOffset(180)]
            public uint dmDisplayFlags;
            [FieldOffset(184)]
            public uint dmDisplayFrequency;
        }
 
        [StructLayout(LayoutKind.Sequential)]
        public struct POINTL
        {
            public int X;
            public int Y;
        }
 
        public enum TernaryRasterOperations : uint
        {
            /// <summary>dest = source</summary> 
            SRCCOPY = 0x00CC0020,
            /// <summary>dest = source OR dest</summary> 
            SRCPAINT = 0x00EE0086,
            /// <summary>dest = source AND dest</summary> 
            SRCAND = 0x008800C6,
            /// <summary>dest = source XOR dest</summary> 
            SRCINVERT = 0x00660046,
            /// <summary>dest = source AND (NOT dest)</summary> 
            SRCERASE = 0x00440328,
            /// <summary>dest = (NOT source)</summary> 
            NOTSRCCOPY = 0x00330008,
            /// <summary>dest = (NOT src) AND (NOT dest)</summary> 
            NOTSRCERASE = 0x001100A6,
            /// <summary>dest = (source AND pattern)</summary> 
            MERGECOPY = 0x00C000CA,
            /// <summary>dest = (NOT source) OR dest</summary> 
            MERGEPAINT = 0x00BB0226,
            /// <summary>dest = pattern</summary> 
            PATCOPY = 0x00F00021,
            /// <summary>dest = DPSnoo</summary> 
            PATPAINT = 0x00FB0A09,
            /// <summary>dest = pattern XOR dest</summary> 
            PATINVERT = 0x005A0049,
            /// <summary>dest = (NOT dest)</summary> 
            DSTINVERT = 0x00550009,
            /// <summary>dest = BLACK</summary> 
            BLACKNESS = 0x00000042,
            /// <summary>dest = WHITE</summary> 
            WHITENESS = 0x00FF0062
        }
 
        public static int GetScreenCount()
        {
            return System.Windows.Forms.Screen.AllScreens.Length;
        }
 
        public static List<DISPLAY_DEVICE> GetAllDisplayDevices()
        {
            List<DISPLAY_DEVICE> listAllDevices = new List<DISPLAY_DEVICE>();
            DISPLAY_DEVICE displayDevice = new DISPLAY_DEVICE();
            for (uint i = 0; i < System.Windows.Forms.Screen.AllScreens.Length; i++)
            {
                displayDevice.cb = 714;
                EnumDisplayDevices(System.Windows.Forms.Screen.AllScreens[i].DeviceName, i, ref displayDevice, 0);
                listAllDevices.Add(displayDevice);
            }
            return listAllDevices;
        }
 
        public static DEVMODE GetCurrentScreenMode(int screenIndex)
        {
            DEVMODE devmode = new DEVMODE();
            devmode.dmSize = (ushort)Marshal.SizeOf(typeof(DEVMODE));
            EnumDisplaySettingsExW(System.Windows.Forms.Screen.AllScreens[screenIndex].DeviceName, ENUM_CURRENT_SETTINGS, out devmode, 0);
            return devmode;
        }
 
        public static List<DEVMODE> GetAllScreenMode(int screenIndex)
        {
            List<DEVMODE> listAllScreenMode = new List<DEVMODE>();
            uint i = 0;
            DEVMODE devmode = new DEVMODE();
            devmode.dmSize = (ushort)Marshal.SizeOf(typeof(DEVMODE));
            while (EnumDisplaySettingsExW(System.Windows.Forms.Screen.AllScreens[screenIndex].DeviceName, i, out devmode, 0))
            {
                listAllScreenMode.Add(devmode);
                i++;
            }
            listAllScreenMode.Sort((x, y) => x.dmPelsWidth < y.dmPelsWidth ? -1 : x.dmPelsWidth > y.dmPelsWidth ? 1 : x.dmPelsHeight < y.dmPelsHeight ? -1 : x.dmPelsHeight > y.dmPelsHeight ? 1 : x.dmBitsPerPel < y.dmBitsPerPel ? -1 : x.dmBitsPerPel > y.dmBitsPerPel ? 1 : x.dmDisplayFrequency < y.dmDisplayFrequency ? -1 : x.dmDisplayFrequency > y.dmDisplayFrequency ? 1 : 0);
            int k = 0;
            while (k < listAllScreenMode.Count - 1)
            {
                if (listAllScreenMode[k].dmPelsWidth == listAllScreenMode[k + 1].dmPelsWidth && listAllScreenMode[k].dmPelsHeight == listAllScreenMode[k + 1].dmPelsHeight && listAllScreenMode[k].dmBitsPerPel == listAllScreenMode[k + 1].dmBitsPerPel && listAllScreenMode[k].dmDisplayFrequency == listAllScreenMode[k + 1].dmDisplayFrequency)
                {
                    listAllScreenMode.RemoveAt(k);
                }
                else
                {
                    k++;
                }
            }
            return listAllScreenMode;
        }
 
        public static void ChangeDisplaySetting(int screenIndex, DEVMODE devMode)
        {
            devMode.dmSize = (ushort)Marshal.SizeOf(typeof(DEVMODE));
            devMode.dmFields = DM_.BITSPERPEL | DM_.PELSWIDTH | DM_.PELSHEIGHT | DM_.DISPLAYFREQUENCY;
            ChangeDisplaySettingsExW(System.Windows.Forms.Screen.AllScreens[screenIndex].DeviceName, ref devMode, IntPtr.Zero, CDS_UPDATEREGISTRY, IntPtr.Zero);
        }
 
    }
}