public IEnumerable <FileOperationWraper> BulkDownload(DownloadModel model) { var folders = new Dictionary <JsonElement, string>(); var files = new Dictionary <JsonElement, string>(); foreach (var fileId in model.FileConvertIds.Where(fileId => !files.ContainsKey(fileId.Key))) { files.Add(fileId.Key, fileId.Value); } foreach (var fileId in model.FileIds.Where(fileId => !files.ContainsKey(fileId))) { files.Add(fileId, string.Empty); } foreach (var folderId in model.FolderIds.Where(folderId => !folders.ContainsKey(folderId))) { folders.Add(folderId, string.Empty); } return(FileStorageService.BulkDownload(folders, files).Select(FileOperationWraperHelper.Get).ToList()); }