Reply to thread

Message

<blockquote data-quote="dannyb0y" data-source="post: 344557" data-attributes="member: 18668">Why thirdparty software?I have written some code that uses windows API to change refresh rate.in my thread <a href="https://forum.team-mediaportal.com/plugins-47/very-simple-refreshrate-changer-39790/" target="_blank">https://forum.team-mediaportal.com/plugins-47/very-simple-refreshrate-changer-39790/</a> you can get the source code.My suggestion is to build a plugin that does not use any thirdparty products to change refresh rate.here is the c# class:using System;using System.Runtime.InteropServices;//http://groups.google.se/group/microsoft.public.dotnet.framework.drawing/browse_thread/thread/2898363a6bc22f30/22e9e76998ccf819?hl=sv&amp;lnk=st&amp;q=refresh+rate+win32+api+c%23#22e9e76998ccf819namespace Monitor{&nbsp; &nbsp; public sealed class Win32&nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; public const int CCHDEVICENAME = 32;&nbsp; &nbsp; &nbsp; &nbsp; public const int CCHFORMNAME = 32;&nbsp; &nbsp; &nbsp; &nbsp; [Flags]&nbsp; &nbsp; &nbsp; &nbsp; public enum DISPLAY_DEVICE_StateFlags : uint&nbsp; &nbsp; &nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; None = 0x00000000,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; DISPLAY_DEVICE_ATTACHED_TO_DESKTOP = 0x00000001,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; DISPLAY_DEVICE_MULTI_DRIVER = 0x00000002,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; DISPLAY_DEVICE_PRIMARY_DEVICE = 0x00000004,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; DISPLAY_DEVICE_MIRRORING_DRIVER = 0x00000008,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; DISPLAY_DEVICE_VGA_COMPATIBLE = 0x00000010,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; DISPLAY_DEVICE_REMOVABLE = 0x00000020,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; DISPLAY_DEVICE_MODESPRUNED = 0x08000000,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; DISPLAY_DEVICE_REMOTE = 0x04000000,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; DISPLAY_DEVICE_DISCONNECT = 0x02000000&nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; [Flags]&nbsp; &nbsp; &nbsp; &nbsp; public enum DEVMODE_Fields : uint&nbsp; &nbsp; &nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; None = 0x00000000,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; DM_POSITION = 0x00000020,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; DM_BITSPERPEL = 0x00040000,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; DM_PELSWIDTH = 0x00080000,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; DM_PELSHEIGHT = 0x00100000,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; DM_DISPLAYFLAGS = 0x00200000,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; DM_DISPLAYFREQUENCY = 0x00400000&nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; [Flags]&nbsp; &nbsp; &nbsp; &nbsp; public enum ChangeDisplaySettings_Flags : uint&nbsp; &nbsp; &nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; None = 0x00000000,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; CDS_UPDATEREGISTRY = 0x00000001,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; CDS_TEST = 0x00000002,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; CDS_FULLSCREEN = 0x00000004,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; CDS_GLOBAL = 0x00000008,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; CDS_SET_PRIMARY = 0x00000010,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; CDS_VIDEOPARAMETERS = 0x00000020,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; CDS_RESET = 0x40000000,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; CDS_NORESET = 0x10000000&nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; public enum ChangeDisplaySettings_Result : int&nbsp; &nbsp; &nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; DISP_CHANGE_SUCCESSFUL = 0,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; DISP_CHANGE_RESTART = 1,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; DISP_CHANGE_FAILED = -1,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; DISP_CHANGE_BADMODE = -2,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; DISP_CHANGE_NOTUPDATED = -3,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; DISP_CHANGE_BADFLAGS = -4,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; DISP_CHANGE_BADPARAM = -5,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; DISP_CHANGE_BADDUALVIEW = -6&nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; public enum EnumDisplaySettings_EnumMode : uint&nbsp; &nbsp; &nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; ENUM_CURRENT_SETTINGS = uint.MaxValue,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; ENUM_REGISTRY_SETTINGS = uint.MaxValue - 1&nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]&nbsp; &nbsp; &nbsp; &nbsp; public class DISPLAY_DEVICE&nbsp; &nbsp; &nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public uint cb = (uint)Marshal.SizeOf(typeof(DISPLAY_DEVICE));&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 32)]&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public string DeviceName = &quot;&quot;;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 128)]&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public string DeviceString = &quot;&quot;;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public DISPLAY_DEVICE_StateFlags StateFlags = 0;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 128)]&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public string DeviceID = &quot;&quot;;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 128)]&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public string DeviceKey = &quot;&quot;;&nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; [StructLayout(LayoutKind.Sequential)]&nbsp; &nbsp; &nbsp; &nbsp; public struct POINTL&nbsp; &nbsp; &nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public POINTL(int x, int y)&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; this.x = x;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; this.y = y;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public int x;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public int y;&nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]&nbsp; &nbsp; &nbsp; &nbsp; public class DEVMODE_Display&nbsp; &nbsp; &nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [MarshalAs(UnmanagedType.ByValTStr, SizeConst = CCHDEVICENAME)]&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public string dmDeviceName = null;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public ushort dmSpecVersion = 0;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public ushort dmDriverVersion = 0;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public ushort dmSize = (ushort)Marshal.SizeOf(typeof(DEVMODE_Display));&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public ushort dmDriverExtra = 0;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public DEVMODE_Fields dmFields = DEVMODE_Fields.None;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public POINTL dmPosition = new POINTL();&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public uint dmDisplayOrientation = 0;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public uint dmDisplayFixedOutput = 0;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public short dmColor = 0;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public short dmDuplex = 0;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public short dmYResolution = 0;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public short dmTTOption = 0;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public short dmCollate = 0;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [MarshalAs(UnmanagedType.ByValTStr, SizeConst = CCHFORMNAME)]&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public string dmFormName = null;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public ushort dmLogPixels = 0;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public uint dmBitsPerPel = 0;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public uint dmPelsWidth = 0;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public uint dmPelsHeight = 0;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public uint dmDisplayFlags = 0;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public uint dmDisplayFrequency = 0;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public uint dmICMMethod = 0;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public uint dmICMIntent = 0;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public uint dmMediaType = 0;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public uint dmDitherType = 0;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public uint dmReserved1 = 0;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public uint dmReserved2 = 0;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public uint dmPanningWidth = 0;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public uint dmPanningHeight = 0;&nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; [DllImport(&quot;user32.dll&quot;, CharSet = CharSet.Unicode)]&nbsp; &nbsp; &nbsp; &nbsp; public extern static int EnumDisplayDevices([In] string lpDevice, [In] &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; uint iDevNum, [In][Out] DISPLAY_DEVICE lpDisplayDevice, [In] uint dwFlags);&nbsp; &nbsp; &nbsp; &nbsp; [DllImport(&quot;user32.dll&quot;, CharSet = CharSet.Unicode)]&nbsp; &nbsp; &nbsp; &nbsp; public extern static int EnumDisplaySettingsEx([In] string lpszDeviceName,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [In] EnumDisplaySettings_EnumMode iModeNum, [In][Out] DEVMODE_Display&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; lpDevMode, [In] uint dwFlags);&nbsp; &nbsp; &nbsp; &nbsp; [DllImport(&quot;user32.dll&quot;, CharSet = CharSet.Unicode)]&nbsp; &nbsp; &nbsp; &nbsp; public extern static ChangeDisplaySettings_Result&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; ChangeDisplaySettingsEx([In] string lpszDeviceName, [In] DEVMODE_Display&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; lpDevMode, [In] IntPtr hwnd, [In] ChangeDisplaySettings_Flags dwFlags, [In] &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; IntPtr lParam);&nbsp; &nbsp; &nbsp; &nbsp; public static void CycleRefreshRate(uint monitorIndex, uint refreshRate)&nbsp; &nbsp; &nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Monitor.Win32.DISPLAY_DEVICE displayDevice = new Monitor.Win32.DISPLAY_DEVICE();&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; int result = Monitor.Win32.EnumDisplayDevices(null, monitorIndex, displayDevice, 0);&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; if (result != 0)&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Monitor.Win32.DEVMODE_Display devMode = new Monitor.Win32.DEVMODE_Display();&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; devMode.dmFields = Monitor.Win32.DEVMODE_Fields.DM_DISPLAYFREQUENCY;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; devMode.dmDisplayFrequency = refreshRate;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Monitor.Win32.ChangeDisplaySettings_Result r = Monitor.Win32.ChangeDisplaySettingsEx(displayDevice.DeviceName, devMode,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp; IntPtr.Zero, Monitor.Win32.ChangeDisplaySettings_Flags.None, IntPtr.Zero);&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; }}</blockquote>

[QUOTE="dannyb0y, post: 344557, member: 18668"] [b]Why thirdparty software?[/b] I have written some code that uses windows API to change refresh rate. in my thread [url]https://forum.team-mediaportal.com/plugins-47/very-simple-refreshrate-changer-39790/[/url] you can get the source code. My suggestion is to build a plugin that does not use any thirdparty products to change refresh rate. here is the c# class: using System; using System.Runtime.InteropServices; //http://groups.google.se/group/microsoft.public.dotnet.framework.drawing/browse_thread/thread/2898363a6bc22f30/22e9e76998ccf819?hl=sv&lnk=st&q=refresh+rate+win32+api+c%23#22e9e76998ccf819 namespace Monitor { public sealed class Win32 { public const int CCHDEVICENAME = 32; public const int CCHFORMNAME = 32; [Flags] public enum DISPLAY_DEVICE_StateFlags : uint { None = 0x00000000, DISPLAY_DEVICE_ATTACHED_TO_DESKTOP = 0x00000001, DISPLAY_DEVICE_MULTI_DRIVER = 0x00000002, DISPLAY_DEVICE_PRIMARY_DEVICE = 0x00000004, DISPLAY_DEVICE_MIRRORING_DRIVER = 0x00000008, DISPLAY_DEVICE_VGA_COMPATIBLE = 0x00000010, DISPLAY_DEVICE_REMOVABLE = 0x00000020, DISPLAY_DEVICE_MODESPRUNED = 0x08000000, DISPLAY_DEVICE_REMOTE = 0x04000000, DISPLAY_DEVICE_DISCONNECT = 0x02000000 } [Flags] public enum DEVMODE_Fields : uint { None = 0x00000000, DM_POSITION = 0x00000020, DM_BITSPERPEL = 0x00040000, DM_PELSWIDTH = 0x00080000, DM_PELSHEIGHT = 0x00100000, DM_DISPLAYFLAGS = 0x00200000, DM_DISPLAYFREQUENCY = 0x00400000 } [Flags] public enum ChangeDisplaySettings_Flags : uint { None = 0x00000000, CDS_UPDATEREGISTRY = 0x00000001, CDS_TEST = 0x00000002, CDS_FULLSCREEN = 0x00000004, CDS_GLOBAL = 0x00000008, CDS_SET_PRIMARY = 0x00000010, CDS_VIDEOPARAMETERS = 0x00000020, CDS_RESET = 0x40000000, CDS_NORESET = 0x10000000 } public enum ChangeDisplaySettings_Result : int { DISP_CHANGE_SUCCESSFUL = 0, DISP_CHANGE_RESTART = 1, DISP_CHANGE_FAILED = -1, DISP_CHANGE_BADMODE = -2, DISP_CHANGE_NOTUPDATED = -3, DISP_CHANGE_BADFLAGS = -4, DISP_CHANGE_BADPARAM = -5, DISP_CHANGE_BADDUALVIEW = -6 } public enum EnumDisplaySettings_EnumMode : uint { ENUM_CURRENT_SETTINGS = uint.MaxValue, ENUM_REGISTRY_SETTINGS = uint.MaxValue - 1 } [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)] public class DISPLAY_DEVICE { public uint cb = (uint)Marshal.SizeOf(typeof(DISPLAY_DEVICE)); [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 32)] public string DeviceName = ""; [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 128)] public string DeviceString = ""; public DISPLAY_DEVICE_StateFlags StateFlags = 0; [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 128)] public string DeviceID = ""; [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 128)] public string DeviceKey = ""; } [StructLayout(LayoutKind.Sequential)] public struct POINTL { public POINTL(int x, int y) { this.x = x; this.y = y; } public int x; public int y; } [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)] public class DEVMODE_Display { [MarshalAs(UnmanagedType.ByValTStr, SizeConst = CCHDEVICENAME)] public string dmDeviceName = null; public ushort dmSpecVersion = 0; public ushort dmDriverVersion = 0; public ushort dmSize = (ushort)Marshal.SizeOf(typeof(DEVMODE_Display)); public ushort dmDriverExtra = 0; public DEVMODE_Fields dmFields = DEVMODE_Fields.None; public POINTL dmPosition = new POINTL(); public uint dmDisplayOrientation = 0; public uint dmDisplayFixedOutput = 0; public short dmColor = 0; public short dmDuplex = 0; public short dmYResolution = 0; public short dmTTOption = 0; public short dmCollate = 0; [MarshalAs(UnmanagedType.ByValTStr, SizeConst = CCHFORMNAME)] public string dmFormName = null; public ushort dmLogPixels = 0; public uint dmBitsPerPel = 0; public uint dmPelsWidth = 0; public uint dmPelsHeight = 0; public uint dmDisplayFlags = 0; public uint dmDisplayFrequency = 0; public uint dmICMMethod = 0; public uint dmICMIntent = 0; public uint dmMediaType = 0; public uint dmDitherType = 0; public uint dmReserved1 = 0; public uint dmReserved2 = 0; public uint dmPanningWidth = 0; public uint dmPanningHeight = 0; } [DllImport("user32.dll", CharSet = CharSet.Unicode)] public extern static int EnumDisplayDevices([In] string lpDevice, [In] uint iDevNum, [In][Out] DISPLAY_DEVICE lpDisplayDevice, [In] uint dwFlags); [DllImport("user32.dll", CharSet = CharSet.Unicode)] public extern static int EnumDisplaySettingsEx([In] string lpszDeviceName, [In] EnumDisplaySettings_EnumMode iModeNum, [In][Out] DEVMODE_Display lpDevMode, [In] uint dwFlags); [DllImport("user32.dll", CharSet = CharSet.Unicode)] public extern static ChangeDisplaySettings_Result ChangeDisplaySettingsEx([In] string lpszDeviceName, [In] DEVMODE_Display lpDevMode, [In] IntPtr hwnd, [In] ChangeDisplaySettings_Flags dwFlags, [In] IntPtr lParam); public static void CycleRefreshRate(uint monitorIndex, uint refreshRate) { Monitor.Win32.DISPLAY_DEVICE displayDevice = new Monitor.Win32.DISPLAY_DEVICE(); int result = Monitor.Win32.EnumDisplayDevices(null, monitorIndex, displayDevice, 0); if (result != 0) { Monitor.Win32.DEVMODE_Display devMode = new Monitor.Win32.DEVMODE_Display(); devMode.dmFields = Monitor.Win32.DEVMODE_Fields.DM_DISPLAYFREQUENCY; devMode.dmDisplayFrequency = refreshRate; Monitor.Win32.ChangeDisplaySettings_Result r = Monitor.Win32.ChangeDisplaySettingsEx(displayDevice.DeviceName, devMode, IntPtr.Zero, Monitor.Win32.ChangeDisplaySettings_Flags.None, IntPtr.Zero); } } } } [/QUOTE]

Verification