Toggling Focus Assist mode in Win 10 Programmatically

Toggling Focus Assist mode in Win 10 Programmatically

using System.Diagnostics;
using System.Runtime.InteropServices;

namespace ConsoleApp1
{
    internal class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Hello, World!");
            var state = WnfHelper.GetFocusAssistValue();
            Console.WriteLine($"{state.ToString()}");
            Console.ReadLine();
        }
    }

    public static class WnfHelper
    {
        public const ulong WNF_SHEL_QUIETHOURS_ACTIVE_PROFILE_CHANGED = 0x0d83063ea3bf1c75UL;

        [StructLayout(LayoutKind.Sequential)]
        private struct WNF_STATE_NAME
        {
            public uint Data1;

            public uint Data2;
        }

        [DllImport("ntdll.dll", SetLastError = true)]
        private static extern int NtQueryWnfStateData(
                                        ref ulong stateName,
                                        IntPtr typeId,
                                        IntPtr explicitScope,
                                        out uint changeStamp,
                                        byte[] buffer,
                                        ref uint bufferSize);

        public static FocusAssistState GetFocusAssistValue()
        {
            return
                (FocusAssistState)
                    GetWnfStateValue(
                            WNF_SHEL_QUIETHOURS_ACTIVE_PROFILE_CHANGED);
        }

        public static int GetWnfStateValue(ulong stateNameIdent)
        {
            var buffer = new byte[4];  // DWORD
            var bufferSize = (uint)buffer.Length;

            var status =
                NtQueryWnfStateData(
                        ref stateNameIdent,
                        IntPtr.Zero,
                        IntPtr.Zero,
                        out var changeStamp,
                        buffer,
                        ref bufferSize);

            if (status == 0)
            {
                var mode = BitConverter.ToInt32(buffer, 0);

                Debug.WriteLine($"Mode:  '{mode}'");

                return mode;
            }
            else
            {
                Debug.WriteLine($"Failed to read the state value. 'NTSTATUS': '0x{status:X8}'");
            }

            return -1;
        }
    }

    public enum FocusAssistState : uint
    {
        Off = 0,
        Game = 1,
        Fullscreen = 2,
    }
}

 

 

https://martinsuchan.github.io/ApiPeek/Diffs/win11.22526.to.win11.22572.fulldiff.html

https://helpdeskgeek.com/what-is-focus-assist-in-windows-11-and-how-to-use-it/

https://stackoverflow.com/questions/55477041/toggling-focus-assist-mode-in-win-10-programmatically