[Unity][Windows] Select a file in the file explorer

SelectAFileInFileExplorer.cs

using System;
using System.IO;
using System.Runtime.InteropServices;
using UnityEditor;
using UnityEngine;

internal static class Test {
    [MenuItem("Help/Test/SHOpenFolderAndSelectItems")]
    private static void MenuItem_MyMenu_SHOpenFolderAndSelectItems() {
        string path     = "C:/Windows/system.ini";
        string fullPath = Path.GetFullPath(path);
        SelectInFileExplorer(fullPath);
        Debug.Log($"fullPath={fullPath}");
    }

    private static void SelectInFileExplorer(string fullPath) {
        try {
            IntPtr pidl = Shell32Methods.ILCreateFromPathW(fullPath);
            try {
                int errorCode = Shell32Methods.SHOpenFolderAndSelectItems(pidl, 0, IntPtr.Zero, 0);
                Debug.Log($"errorCode={errorCode}");
            }
            finally {
                Shell32Methods.ILFree(pidl);
            }
        }
        catch {
            // do nothing
        }
    }

    private static class Shell32Methods {
        // https://learn.microsoft.com/en-us/windows/win32/api/shlobj_core/nf-shlobj_core-ilfree
        [DllImport("shell32.dll")]
        public static extern void ILFree(IntPtr pidl);

        // https://learn.microsoft.com/en-us/windows/win32/api/shlobj_core/nf-shlobj_core-ilcreatefrompathw
        [DllImport("shell32.dll", CharSet = CharSet.Unicode)]
        public static extern IntPtr ILCreateFromPathW(string pszPath);

        // https://learn.microsoft.com/en-us/windows/win32/api/shlobj_core/nf-shlobj_core-shopenfolderandselectitems
        [DllImport("shell32.dll")]
        public static extern int SHOpenFolderAndSelectItems(IntPtr pidl, uint cild, IntPtr apidl, uint dwFlags);
    }
}