public bool UpdateMark(string id, string mark) { int rightID; int rightMark; if (Int32.TryParse(id, out rightID) && Int32.TryParse(mark, out rightMark)) { if (GetFileById(rightID) != null) { if (rightMark >= 0 && rightMark <= 10) { _fileDao.UpdateMark(Int32.Parse(id), Int32.Parse(mark)); return(true); } else { Console.WriteLine("Incorrect MARK! Mark must be between 0 and 10"); return(false); } } else { Console.WriteLine("Can't find file"); return(false); } } else { Console.WriteLine("Incorrect ID or MARK (not number"); return(false); } }