public string GetFileName() { string extension; if (!TLString.IsNullOrEmpty(Url)) { extension = Path.GetExtension(Url.ToString()); if (!string.IsNullOrEmpty(extension)) { return(ResultId + extension); } } if (!TLString.IsNullOrEmpty(ContentUrl)) { extension = Path.GetExtension(ContentUrl.ToString()); if (!string.IsNullOrEmpty(extension)) { return(ResultId + extension); } } return(ResultId + TLUtils.ContentTypeToFileExt(ContentType)); }