public void UpdateAttendance(DateTime date, int classId, List <List <BCAttendance> > attendance, List <BCTeacherSubject> teacher) { _attendanceRepo.DeleteDaysAttendance(date, classId); int index = 0; List <BCAttendance> masterList = new List <BCAttendance>(); foreach (List <BCAttendance> a in attendance) { int id = teacher[index].BCTeacherSubjectId; foreach (BCAttendance status in a) { status.BCTeacherSubjectId = id; status.Date = date; masterList.Add(status); } index++; } masterList = masterList.Where(a => a.BCTeacherSubjectId != 0).ToList(); _attendanceRepo.AddAttendance(masterList); }