[C#] .NET 6 で、GetActiveObject を使って VS/Access/Word/Excel/PowerPoint で開いているドキュメントのパスを得る

Program.vb

// this code for .NET 6
using System;
using System.Runtime.InteropServices;
using System.Runtime.InteropServices.ComTypes;

if (OperatingSystem.IsWindows())
{
    // VS2022=17.0, VS2019=16.0, VS2017=15.0, VS2015=14.0, VS2013=12.0, VS2012=11.0, VS2010=10.0, VS2008=9.0, VS2005=8.0, VS2003=7.1, VS2002=7
    foreach (var v in new []{ "", ".17.0", ".16.0", ".15.0", ".14.0", ".12.0", "11.0", ".10.0", ".9.0"})
    {
        dynamic? dte = Example.GetObject($"VisualStudio.DTE{v}");
        if (dte is not null)
        {
            try
            {
                var solution = dte.Solution;
                Console.WriteLine($"Visual Studio{v}: {solution?.FullName}");
                Marshal.FinalReleaseComObject(solution);
            }
            catch (Exception) { }
            Marshal.FinalReleaseComObject(dte);
        }
    }

    dynamic? accessApp = Example.GetObject("Access.Application");
    if (accessApp is not null)
    {
        var database = accessApp.CurrentDb();       // プロパティではなくメソッド
        var accessHwnd = accessApp.hWndAccessApp(); // プロパティではなくメソッド
        Console.WriteLine($"Access: {database.Name}, hWnd=0x{accessHwnd:X}");
        var screen = accessApp.Screen;
        var form = default(dynamic);
        try
        {
            if ((form = screen?.ActiveForm) is not null)
            {
                Console.WriteLine($"\thWnd=0x{form.Hwnd:X}, Caption={form.Caption}");
                Marshal.ReleaseComObject(form);
            }
        }
        catch (Exception) { }
        finally
        {
            if (form is not null)
            {
                Marshal.FinalReleaseComObject(form);
            }
        }
        Marshal.FinalReleaseComObject(screen);
        Marshal.FinalReleaseComObject(database);
        Marshal.FinalReleaseComObject(accessApp);
    }

    dynamic? wordApp = Example.GetObject("Word.Application");
    if (wordApp is not null)
    {
        var document = wordApp.ActiveDocument;
        Console.WriteLine($"Word: Saved = {document.Saved}, {document.FullName}");
        if (wordApp.ActiveWindow is { } window)
        {
            Console.WriteLine($"\tHwnd=0x{window.Hwnd:X}, Caption={window.Caption}");
            Marshal.ReleaseComObject(window);
        }
        Marshal.FinalReleaseComObject(document);
        Marshal.FinalReleaseComObject(wordApp);
    }

    dynamic? excelApp = Example.GetObject("Excel.Application");
    if (excelApp is not null)
    {
        var book = excelApp.ActiveWorkbook;
        Console.WriteLine($"Excel: Instance={excelApp.HinstancePtr}, Saved = {book.Saved}, {book.FullName}");
        if (excelApp.ActiveWindow is { } window)
        {
            Console.WriteLine($"\tHwnd=0x{window.Hwnd:X}, Caption={window.Caption}");
            Marshal.ReleaseComObject(window);
        }
        Marshal.FinalReleaseComObject(book);
        Marshal.FinalReleaseComObject(excelApp);
    }

    dynamic? pptApp = Example.GetObject("PowerPoint.Application");
    if (pptApp is not null)
    {
        var presentation = pptApp.ActivePresentation;
        Console.WriteLine($"PowerPoint: Saved = {presentation.Saved}, {presentation.FullName}");
        if (pptApp.ActiveWindow is { } window)
        {
            // Console.WriteLine($"\tHWND=0x{window.HWND:X}, Caption={window.Caption}");
            Console.WriteLine($"\tCaption={window.Caption}");
            Marshal.ReleaseComObject(window);
        }
        Marshal.FinalReleaseComObject(presentation);
        Marshal.FinalReleaseComObject(pptApp);
    }
}

static class Example
{
    public static object? GetObject(string progID)
    {
        try
        {
            CLSIDFromProgID(progID, out Guid clsid);
            return GetActiveObject(ref clsid, IntPtr.Zero);
        }
        catch
        {
            return null;
        }
    }

    [DllImport("ole32.dll", PreserveSig = false)]
    static extern void CLSIDFromProgID([MarshalAs(UnmanagedType.LPWStr)] string progId, out Guid clsid);

    [DllImport("oleaut32.dll", PreserveSig = false)]
    [return: MarshalAs(UnmanagedType.Interface)]
    static extern object GetActiveObject(ref Guid rclsid, IntPtr reserved);
}