//public int Save(EnrollStudent enrollStudent)
        //{
        //    EnrollStudentGateway enrollStudentGateway = new EnrollStudentGateway();
        //    return enrollStudentGateway.Save(enrollStudent);
        //}


        public string Save(EnrollStudent enrollStudent)
        {
            EnrollStudent aenrollStudent =
                GetEnrollCourses.ToList()
                .Find(
                    st =>
                    st.StudentId == enrollStudent.StudentId &&
                    st.CourseId == enrollStudent.CourseId);

            if (aenrollStudent == null)
            {
                if (enrollStudentGateway.Save(enrollStudent) > 0)
                {
                    return("Saved Sucessfully!");
                }
                return("Failed to save");
            }
            return("This course already taken by the student");
        }
        public string Save(EnrollStudentInCourse enrollStudentInCourse)
        {
            EnrollStudentInCourse enrollStudent =
                GetEnrollCourses.ToList()
                .Find(
                    st =>
                    (st.StudentId == enrollStudentInCourse.StudentId &&
                     st.CourseId == enrollStudentInCourse.CourseId) && (st.Status));

            if (enrollStudent == null)
            {
                if (studentGateway.Insert(enrollStudentInCourse) > 0)
                {
                    return("Saved Sucessfully!");
                }
                return("Failed to save");
            }

            return("This course already taken by the student");
        }