public async Task <ActionResult <ResultData> > GetScs()
{
var scs = await _studentCourseRepository.GetAllEntitiesAsIQueryable()
.Include(x => x.Student)
.Include(x => x.Course).ToListAsync();
var dtos = _mapper.Map <IEnumerable <StudentCourseDto> >(scs);
return(new ResultData(ReturnCode.Succeed, scs.Count(), "选课信息", dtos));
}