public IHttpActionResult PostGradeByAdmin(string studentId, int subjectId, [FromBody] Grade grade) { if (studentsService.ExistsID(studentId) == false || subjectsService.ExistsID(subjectId) == false) { return(NotFound()); } if (studentsService.StudentHasSubject(studentId, subjectId) == false) { return(NotFound()); } return(Created("AdminGaveGrade", adminsService.PostGradeToStudent(studentId, subjectId, grade))); }