protected override void OnClick()
        {
            // set
            m_pApp = (IGxApplication)CustomGxFilter_CS.ArcCatalog.Application;
            IGxCatalog      pCat        = null;
            IGxFileFilter   pFileFilter = null;
            IEnumGxObject   pSelection  = null;
            IGxDialog       pDlg        = null;
            IGxObjectFilter pFilter     = null;

            try
            {
                pDlg        = new GxDialog();
                pCat        = pDlg.InternalCatalog;
                pFileFilter = pCat.FileFilter;
                if (pFileFilter.FindFileType("py") < 0)
                {
                    //enter the third parameter with the location of the icon as needed
                    pFileFilter.AddFileType("PY", "Python file", "");
                }

                pFilter               = new CustomGxFilter_CS.CustomFilter();
                pDlg.ObjectFilter     = pFilter;
                pDlg.Title            = "Please select a .Py file";
                pDlg.AllowMultiSelect = true;
                pDlg.DoModalOpen(0, out pSelection);
            }
            catch (Exception ex)
            {
                System.Windows.Forms.MessageBox.Show(ex.ToString());
            }
            finally
            {
                pCat        = null;
                pFileFilter = null;
                pSelection  = null;
                pDlg        = null;
                pFilter     = null;
            }
        }
        protected override void OnClick()
        {
            // set
            m_pApp = (IGxApplication)CustomGxFilter_CS.ArcCatalog.Application;
            IGxCatalog pCat = null;
            IGxFileFilter pFileFilter = null;
            IEnumGxObject pSelection = null;
            IGxDialog pDlg = null;
            IGxObjectFilter pFilter = null;
            try
            {
                pDlg = new GxDialog();
                pCat = pDlg.InternalCatalog ;
                pFileFilter = pCat.FileFilter;
                if (pFileFilter.FindFileType("py") < 0)
                {
                    //enter the third parameter with the location of the icon as needed
                    pFileFilter.AddFileType("PY", "Python file", "");
                }

                pFilter = new CustomGxFilter_CS.CustomFilter();
                pDlg.ObjectFilter = pFilter;
                pDlg.Title = "Please select a .Py file";
                pDlg.AllowMultiSelect = true;
                pDlg.DoModalOpen(0, out pSelection);
            }
            catch (Exception ex)
            {
                System.Windows.Forms.MessageBox.Show(ex.ToString());
            }
            finally
            {
                pCat = null;
                pFileFilter = null;
                pSelection = null;
                pDlg = null;
                pFilter = null;
            }
        }