public static string AutoMaNV() { string id = NhanVienDAL.GetLastID().Trim(); if (id == "") { return("MANV000001"); } int nextID = int.Parse(id.Remove(0, "MANV".Length)) + 1; id = "00000" + nextID.ToString(); id = id.Substring(id.Length - 6, 6); return("MANV" + id); }