public void AssignToSubject(int studentId, int subjectId)
        {
            StudentsXSubject entity = new StudentsXSubject()
            {
                SubjectId = subjectId,
                StudentId = studentId
            };

            _studentXSubjectRepository.Add(entity);
        }
        public void AssignToSubject(int studentId, int subjectId)
        {
            StudentsXSubject entity = new StudentsXSubject()
            {
                StudentId = studentId,
                SubjectId = subjectId
            };

            _trainingDBContext.StudentsXSubjects.Add(entity);
            _trainingDBContext.SaveChanges();
        }