CSL_Test__1.MainWindow.dataGridView_DragDrop C# (CSharp) Метод

        private void dataGridView_DragDrop(object sender, DragEventArgs e)
        {
            al = new ArrayList();
            files = (string[])e.Data.GetData(DataFormats.FileDrop);
            dataGridViewProgressBar.Visible = true;
            StatusLabel.Visible = true;

            foreach (string file in files)
            {
                string extension = Path.GetExtension(file);
                if (Path.GetExtension(file).Equals(".zip") || Path.GetExtension(file).Equals(".rar"))
                {
                    foreach (string unzipped in DirectoryHandler.UnzipFile(file))
                        al.Add(unzipped);
                }
                else if (Path.GetExtension(file).Equals(".torrent"))
                {
                    al.Add(file);
                }
            }

            lock (lockingobject)
            {
                tb.RunWorkerAsync(al);
            }
        }