private async Task UnEnrollSteveFromCourse(ManyToManyContext ctx) { StudentCourse steveAndDnp = ctx.Students. Where(s => s.StudentNum == 123456) .SelectMany(student => student.StudentCourses). First(studentCourse => studentCourse.Course.CourseCode.Equals("IT-SDJ2-A20")); ctx.Remove(steveAndDnp); await ctx.SaveChangesAsync(); }
private async Task EnrollSteveInDNP(ManyToManyContext ctx, string courseCode) { Student steve = await ctx.Students.FirstAsync(s => s.StudentNum == 123456); Course dnp = await ctx.Courses.FirstAsync(c => c.CourseCode.Equals(courseCode)); StudentCourse sc = new StudentCourse { Course = dnp, Student = steve }; steve.StudentCourses = new List <StudentCourse>(); steve.StudentCourses.Add(sc); ctx.Update(steve); // ctx.Set<StudentCourse>().Add(sc); This is an alternative await ctx.SaveChangesAsync(); }