Show detailed Folder Browser from a PropertyGrid

Here is a custom UITypeEditor that allows you to use the Vista Folder Browser:

You can use it like any other editor:

[EditorAttribute(typeof(FolderNameEditor2), typeof(System.Drawing.Design.UITypeEditor))]

It relies on a custom FolderBrowser2 class that I have written for the occasion. Of course, this will work only on Windows Vista and higher. On previous Windows version, there is no other folder browser than the simple one.

public class FolderNameEditor2 : UITypeEditor
{
    public override UITypeEditorEditStyle GetEditStyle(ITypeDescriptorContext context)
    {
        return UITypeEditorEditStyle.Modal;
    }

    public override object EditValue(ITypeDescriptorContext context, IServiceProvider provider, object value)
    {
        FolderBrowser2 browser = new FolderBrowser2();
        if (value != null)
        {
            browser.DirectoryPath = string.Format("{0}", value);
        }

        if (browser.ShowDialog(null) == DialogResult.OK)
            return browser.DirectoryPath;

        return value;
    }
}

public class FolderBrowser2
{
    public string DirectoryPath { get; set; }

    public DialogResult ShowDialog(IWin32Window owner)
    {
        IntPtr hwndOwner = owner != null ? owner.Handle : GetActiveWindow();

        IFileOpenDialog dialog = (IFileOpenDialog)new FileOpenDialog();
        try
        {
            IShellItem item;
            if (!string.IsNullOrEmpty(DirectoryPath))
            {
                IntPtr idl;
                uint atts = 0;
                if (SHILCreateFromPath(DirectoryPath, out idl, ref atts) == 0)
                {
                    if (SHCreateShellItem(IntPtr.Zero, IntPtr.Zero, idl, out item) == 0)
                    {
                        dialog.SetFolder(item);
                    }
                    Marshal.FreeCoTaskMem(idl);
                }
            }
            dialog.SetOptions(FOS.FOS_PICKFOLDERS | FOS.FOS_FORCEFILESYSTEM);
            uint hr = dialog.Show(hwndOwner);
            if (hr == ERROR_CANCELLED)
                return DialogResult.Cancel;

            if (hr != 0)
                return DialogResult.Abort;

            dialog.GetResult(out item);
            string path;
            item.GetDisplayName(SIGDN.SIGDN_FILESYSPATH, out path);
            DirectoryPath = path;
            return DialogResult.OK;
        }
        finally
        {
            Marshal.ReleaseComObject(dialog);
        }
    }

    [DllImport("shell32.dll")]
    private static extern int SHILCreateFromPath([MarshalAs(UnmanagedType.LPWStr)] string pszPath, out IntPtr ppIdl, ref uint rgflnOut);

    [DllImport("shell32.dll")]
    private static extern int SHCreateShellItem(IntPtr pidlParent, IntPtr psfParent, IntPtr pidl, out IShellItem ppsi);

    [DllImport("user32.dll")]
    private static extern IntPtr GetActiveWindow();

    private const uint ERROR_CANCELLED = 0x800704C7;

    [ComImport]
    [Guid("DC1C5A9C-E88A-4dde-A5A1-60F82A20AEF7")]
    private class FileOpenDialog
    {
    }

    [ComImport]
    [Guid("42f85136-db7e-439c-85f1-e4075d135fc8")]
    [InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
    private interface IFileOpenDialog
    {
        [PreserveSig]
        uint Show([In] IntPtr parent); // IModalWindow
        void SetFileTypes();  // not fully defined
        void SetFileTypeIndex([In] uint iFileType);
        void GetFileTypeIndex(out uint piFileType);
        void Advise(); // not fully defined
        void Unadvise();
        void SetOptions([In] FOS fos);
        void GetOptions(out FOS pfos);
        void SetDefaultFolder(IShellItem psi);
        void SetFolder(IShellItem psi);
        void GetFolder(out IShellItem ppsi);
        void GetCurrentSelection(out IShellItem ppsi);
        void SetFileName([In, MarshalAs(UnmanagedType.LPWStr)] string pszName);
        void GetFileName([MarshalAs(UnmanagedType.LPWStr)] out string pszName);
        void SetTitle([In, MarshalAs(UnmanagedType.LPWStr)] string pszTitle);
        void SetOkButtonLabel([In, MarshalAs(UnmanagedType.LPWStr)] string pszText);
        void SetFileNameLabel([In, MarshalAs(UnmanagedType.LPWStr)] string pszLabel);
        void GetResult(out IShellItem ppsi);
        void AddPlace(IShellItem psi, int alignment);
        void SetDefaultExtension([In, MarshalAs(UnmanagedType.LPWStr)] string pszDefaultExtension);
        void Close(int hr);
        void SetClientGuid();  // not fully defined
        void ClearClientData();
        void SetFilter([MarshalAs(UnmanagedType.Interface)] IntPtr pFilter);
        void GetResults([MarshalAs(UnmanagedType.Interface)] out IntPtr ppenum); // not fully defined
        void GetSelectedItems([MarshalAs(UnmanagedType.Interface)] out IntPtr ppsai); // not fully defined
    }

    [ComImport]
    [Guid("43826D1E-E718-42EE-BC55-A1E261C37BFE")]
    [InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
    private interface IShellItem
    {
        void BindToHandler(); // not fully defined
        void GetParent(); // not fully defined
        void GetDisplayName([In] SIGDN sigdnName, [MarshalAs(UnmanagedType.LPWStr)] out string ppszName);
        void GetAttributes();  // not fully defined
        void Compare();  // not fully defined
    }

    private enum SIGDN : uint
    {
        SIGDN_DESKTOPABSOLUTEEDITING = 0x8004c000,
        SIGDN_DESKTOPABSOLUTEPARSING = 0x80028000,
        SIGDN_FILESYSPATH = 0x80058000,
        SIGDN_NORMALDISPLAY = 0,
        SIGDN_PARENTRELATIVE = 0x80080001,
        SIGDN_PARENTRELATIVEEDITING = 0x80031001,
        SIGDN_PARENTRELATIVEFORADDRESSBAR = 0x8007c001,
        SIGDN_PARENTRELATIVEPARSING = 0x80018001,
        SIGDN_URL = 0x80068000
    }

    [Flags]
    private enum FOS
    {
        FOS_ALLNONSTORAGEITEMS = 0x80,
        FOS_ALLOWMULTISELECT = 0x200,
        FOS_CREATEPROMPT = 0x2000,
        FOS_DEFAULTNOMINIMODE = 0x20000000,
        FOS_DONTADDTORECENT = 0x2000000,
        FOS_FILEMUSTEXIST = 0x1000,
        FOS_FORCEFILESYSTEM = 0x40,
        FOS_FORCESHOWHIDDEN = 0x10000000,
        FOS_HIDEMRUPLACES = 0x20000,
        FOS_HIDEPINNEDPLACES = 0x40000,
        FOS_NOCHANGEDIR = 8,
        FOS_NODEREFERENCELINKS = 0x100000,
        FOS_NOREADONLYRETURN = 0x8000,
        FOS_NOTESTFILECREATE = 0x10000,
        FOS_NOVALIDATE = 0x100,
        FOS_OVERWRITEPROMPT = 2,
        FOS_PATHMUSTEXIST = 0x800,
        FOS_PICKFOLDERS = 0x20,
        FOS_SHAREAWARE = 0x4000,
        FOS_STRICTFILETYPES = 4
    }
}