/// <summary>
        /// On Click Merge Filter Button
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void btnMergeFilter_Click(object sender, EventArgs e)
        {
            //set the defaults if not already set
            if (_assetfilters.DefaultsNotSet)
            {
                var dir = new DirectoryInfo(AppDomain.CurrentDomain.BaseDirectory);
                _assetfilters.FillRolesFilterHolderFromDir(dir);
            }
            try
            {
                Cursor.Current = Cursors.WaitCursor;
                FilterDlg filterDlg;
                var       fileExt = Path.GetExtension(txtPath.Text);

                if (fileExt != null && fileExt.Equals(".xbimf", StringComparison.OrdinalIgnoreCase))
                {
                    var fedFilters = _assetfilters.SetFedModelFilter(MapRefModelsRoles);
                    filterDlg = new FilterDlg(_assetfilters, true, fedFilters);
                }
                else
                {
                    MapRefModelsRoles.Clear();
                    var roles = SetRoles();
                    _assetfilters.ApplyRoleFilters(roles);
                    filterDlg = new FilterDlg(_assetfilters, true);
                }
                filterDlg.ShowDialog();
            }
            finally
            {
                Cursor.Current = Cursors.Default;
            }
        }
        /// <summary>
        /// On Click Class filter Button
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void btnClassFilter_Click(object sender, EventArgs e)
        {
            var dir = new DirectoryInfo(AppDomain.CurrentDomain.BaseDirectory);

            //set the defaults if not already set
            if (_assetfilters.DefaultsNotSet)
            {
                _assetfilters.FillRolesFilterHolderFromDir(dir);
            }
            try
            {
                Cursor.Current = Cursors.WaitCursor;
                var filterDlg = new FilterDlg(_assetfilters);
                if (filterDlg.ShowDialog() != DialogResult.OK)
                {
                    return;
                }
                _assetfilters = filterDlg.RolesFilters;
                _assetfilters.WriteXmlRolesFilterHolderToDir(dir);
            }
            finally
            {
                Cursor.Current = Cursors.Default;
            }
        }