public async Task AddTeachersToCourse(int courseId, int techerId)
{
CoursesTeachers courseTeachers = new CoursesTeachers
{
CourseId = courseId,
TeacherId = techerId,
};
await this.coursesTeacherRepository.AddAsync(courseTeachers);
await this.coursesTeacherRepository.SaveChangesAsync();
}
public IActionResult Index()
{
//haal de cursus op met id 1
var courseInDb = _schoolDbContext
.Courses
.SingleOrDefault(c => c.Id == 2);
//haal alle cursussen op
var courses = _schoolDbContext.Courses.ToList();
foreach (var course in courses)
{
Console.WriteLine($"{course.Id}-{course.CourseName}");
}
//selectie op basis van voorwaarden
//vb haal alle cursussen die beginnen met WB
//linq Where
var coursesWb = _schoolDbContext
.Courses
.Where(c => c.CourseName.Contains("WB"))
.OrderBy(c => c.CourseName)
.ToList();
foreach (var courseWb in coursesWb)
{
Console.WriteLine($"{courseWb.Id}-{courseWb.CourseName}");
}
//selectie van veld(en)
//bv enkel de courseName = enkel veld
var courseOnlyTitle = _schoolDbContext
.Courses
.OrderBy(c => c.CourseName)
.Select(c => c.CourseName)//vanaf hier = lijst van string
.ToList();
//select van 2(of meer) velden
//gebruik anoniem object
//vb Id en Coursename
var coursesTitleId = _schoolDbContext
.Courses
.OrderBy(c => c.CourseName)
.Select(c => new { c.CourseName, c.Id })
.ToList();
//ophalen gerelateerde data
//gebruik de include method
//(rechtreeks gerelateerd)
//ThenInclude (onrechtstreeks gerelateerd)
//haal courses met hun teachers op
var coursesTeachers = _schoolDbContext
.Courses
.Include(c => c.Teachers) //join CoursesTeachers
.ThenInclude(ct => ct.Teacher)
.OrderBy(c => c.CourseName) //join met Taachers
.ToList();
foreach (var coursesTeacher in coursesTeachers)
{
Console.WriteLine($"{coursesTeacher?.CourseName}");
foreach (var teacher in coursesTeacher?.Teachers)
{
Console.Write($"{teacher?.Teacher?.TeacherName} ");
}
}
//toevoegen van data
//single object(zonder gerelateerde data)
//var newTeacher = new Teacher();
//newTeacher.TeacherName = "Siegfried Deerdeyn";
//change tracker
// _schoolDbContext.Teachers.Add(newTeacher);
//maak een nieuwe teacher
//maak een nieuwe cursus
//voeg ze toe aan CourseTeachers
//var newTeacher = new Teacher
//{ TeacherName = "Willie Schokkelé",YearlyWage=20000 };
//var newCourse = new Course { CourseName = "CIA", Duration = 20 };
//var courseTeacher = new CoursesTeachers
//{ Course = newCourse, Teacher = newTeacher };
////toevoegen aan de databasecontext
//_schoolDbContext.CoursesTeachers.Add(courseTeacher);
var teacherCourse = new CoursesTeachers
{
CourseId = 1 /*WBA*/, TeacherId = 4/*William Schokkelé*/
};
//toevoegen aan chnge tracker
_schoolDbContext.CoursesTeachers.Add(teacherCourse);
//opslaan gebeurt op het einde
_schoolDbContext.SaveChanges();
return(View());
}
