Add data to a Laravel pivot table - laravel

Question

I have a database with 3 tables : users, events and user_event.
I create my event. Once my event is created, I would like to add users.
How can I add him via a form to add users?
My pivot table contain :
event_id, user_id
Do I need to create a UserEventController?
My model relations :
public function users()
{
return $this->belongsToMany('User')->withPivot('user_event');
}
For create an event :
public function store(Request $request)
{
$this->validate($request, [
'course_name' => 'required|max:255',
'academic_year' => 'required|max:4|min:4',
'exam_session' => 'required',
'date_event' => 'required'
]);
$event = new Event();
$event->course_name = $request->course_name;
$event->academic_year = $request->academic_year;
$event->exam_session = $request->exam_session;
$event->date_event = $request->date_event;
$event->save();
}
Thanks for your help !

Answer 1

So you need to use the attach()method :
$event->users()->attach($userId);
more informations here : Laravel Eloquent - Attach vs Sync

Answer 2

Since the event is already created, you can just use the event object to add an existing user, create a new one, or maybe even sync a list of users.
//create a new user
$event->users()->create(['name' => 'user name', 'email' => 'user email']);
//attach existing user
$event->users()->attach($userId);
//sync multiple existing users passing array of user ids
$event->users()->sync([1,2,4]);
You can see details about all of those methods and a few more here: https://laravel.com/docs/5.7/eloquent-relationships#inserting-and-updating-related-models