public string Save(EnrollCourse enrollCourse) { if (aEnrollCourseGateway.AlreadyEnrolledInCourse(enrollCourse)) { return("Course already enrolled"); } else { int rowAffected = aEnrollCourseGateway.Save(enrollCourse); if (rowAffected > 0) { return("Enrolled Successfully"); } else { return("Enrolled Failed"); } } }