public async Task <string> GetTelegramFile(string accessHash, string id, int version, int size, string type) { try { var buffer = await _telegramService.GetFileAsync( long.Parse(accessHash), long.Parse(id), version, size); string base64String = Convert.ToBase64String(buffer, 0, buffer.Length); return("data:" + type + ";base64," + base64String); } catch { } return(null); }