private void SearchSubtitleFile(VideoFolder item) { if (item.FileType == FileType.Folder) { return; } if ((item as VideoFolderChild).HasSearchSubtitleFile) { return; } dispatcherService.BeginInvokeDispatchAction(new Action(delegate { var itemchild = (VideoFolderChild)item; if (files == null) { files = filecommonhelper.GetSubtitleFiles(item.ParentDirectory.Directory); } itemchild.SubPath = GetSubtitlePath(item); })); }