public StudentSubject GetAssignemnt(int studentSubjectId)
        {
            StudentSubjectDao = new StudentSubjectDao();

            //convert from business object to data access object

            DataAccess.Domain.StudentSubject studentSubjectData = new DataAccess.Domain.StudentSubject { StudentSubjectId = studentSubjectId };

            studentSubjectData = StudentSubjectDao.GetStudentSubject(studentSubjectData);

            // map data objects to business objects

            StudentSubject studentSubject = new StudentSubject() { UserId = studentSubjectData.UserId, SubjectName = studentSubjectData.SubjectName, SubjectDescription = studentSubjectData.SubjectDescription, SubjectCode = studentSubjectData.SubjectCode, StudentSubjectId = studentSubjectData.StudentSubjectId, AssignmentName = studentSubjectData.AssignmentName, Assignment = studentSubjectData.Assignment, AssignmentSize = studentSubjectData.AssignmentSize };

            return studentSubject;
        }