public IActionResult Update(int studentId, int courseId, [FromBody] MarksModel model)
{
var mark = marksRepository.GetById(studentId, courseId);
if (mark == null)
{
return(NotFound("Mark does not exist for this student."));
}
if (model.MarkValue < 6 || model.MarkValue > 10)
{
return(BadRequest("Invalid mark. Allowed values: 6 - 10"));
}
mark.MarkValue = model.MarkValue;
marksRepository.Save();
return(new NoContentResult());
}