public static extern IntPtr SHBrowseForFolder([In] PInvoke.BROWSEINFO lpbi);
        protected override bool RunDialog(IntPtr hWndOwner)
        {
            bool result = false;

            if (_rootFolderLocation == IntPtr.Zero)
            {
                PInvoke.Shell32.SHGetSpecialFolderLocation(hWndOwner, (int)this._rootFolder, ref _rootFolderLocation);
                if (_rootFolderLocation == IntPtr.Zero)
                {
                    PInvoke.Shell32.SHGetSpecialFolderLocation(hWndOwner, 0, ref _rootFolderLocation);
                    if (_rootFolderLocation == IntPtr.Zero)
                    {
                        throw new InvalidOperationException("FolderBrowserDialogNoRootFolder");
                    }
                }
            }
            _hwndEdit = IntPtr.Zero;
            //_uiFlags = 0;
            if (_dontIncludeNetworkFoldersBelowDomainLevel)
            {
                _uiFlags += BrowseFlags.BIF_DONTGOBELOWDOMAIN;
            }
            if (this._newStyle)
            {
                _uiFlags += BrowseFlags.BIF_NEWDIALOGSTYLE;
            }
            if (!this._showNewFolderButton)
            {
                _uiFlags += BrowseFlags.BIF_NONEWFOLDERBUTTON;
            }
            if (this._showEditBox)
            {
                _uiFlags += BrowseFlags.BIF_EDITBOX;
            }
            if (this._showBothFilesAndFolders)
            {
                _uiFlags += BrowseFlags.BIF_BROWSEINCLUDEFILES;
            }


            if (Control.CheckForIllegalCrossThreadCalls && (Application.OleRequired() != ApartmentState.STA))
            {
                throw new ThreadStateException("DebuggingException: ThreadMustBeSTA");
            }
            IntPtr pidl    = IntPtr.Zero;
            IntPtr hglobal = IntPtr.Zero;
            IntPtr pszPath = IntPtr.Zero;

            try
            {
                PInvoke.BROWSEINFO browseInfo = new PInvoke.BROWSEINFO();
                hglobal                   = Marshal.AllocHGlobal(MAX_PATH * Marshal.SystemDefaultCharSize);
                pszPath                   = Marshal.AllocHGlobal(MAX_PATH * Marshal.SystemDefaultCharSize);
                this._callback            = new PInvoke.BrowseFolderCallbackProc(this.FolderBrowserCallback);
                browseInfo.pidlRoot       = _rootFolderLocation;
                browseInfo.Owner          = hWndOwner;
                browseInfo.pszDisplayName = hglobal;
                browseInfo.Title          = this._descriptionText;
                browseInfo.Flags          = _uiFlags;
                browseInfo.callback       = this._callback;
                browseInfo.lParam         = IntPtr.Zero;
                browseInfo.iImage         = 0;
                pidl = PInvoke.Shell32.SHBrowseForFolder(browseInfo);
                if (((_uiFlags & BrowseFlags.BIF_BROWSEFORPRINTER) == BrowseFlags.BIF_BROWSEFORPRINTER) ||
                    ((_uiFlags & BrowseFlags.BIF_BROWSEFORCOMPUTER) == BrowseFlags.BIF_BROWSEFORCOMPUTER))
                {
                    this._selectedPath = Marshal.PtrToStringAuto(browseInfo.pszDisplayName);
                    result             = true;
                }
                else
                {
                    if (pidl != IntPtr.Zero)
                    {
                        PInvoke.Shell32.SHGetPathFromIDList(pidl, pszPath);
                        this._selectedPathNeedsCheck = true;
                        this._selectedPath           = Marshal.PtrToStringAuto(pszPath);
                        result = true;
                    }
                }
            }
            finally
            {
                PInvoke.IMalloc sHMalloc = GetSHMalloc();
                sHMalloc.Free(_rootFolderLocation);
                _rootFolderLocation = IntPtr.Zero;
                if (pidl != IntPtr.Zero)
                {
                    sHMalloc.Free(pidl);
                }
                if (pszPath != IntPtr.Zero)
                {
                    Marshal.FreeHGlobal(pszPath);
                }
                if (hglobal != IntPtr.Zero)
                {
                    Marshal.FreeHGlobal(hglobal);
                }
                this._callback = null;
            }
            return(result);
        }