Laravel 5.2有很多关系问题

Question

I have 3 tables: orders, codes, events

I want to be able to pull all events that an order has, but there's an intermediary table that acts as a pivot table. I've been trying to use hasManyThrough and belongsToMany (along with withPivot) without any luck.

Examples:

public function events()
{
    return $this->belongsToMany('events'); // tried this, fails
    return $this->hasManyThrough('events', 'codes'); // tried this, fails
    return $this->hasManyThrough('events', 'codes', 'event_id', 'id'); // tried this, fails
}

Any pointers would be great!

Answer 1

That's a belongsToMany setup. First, the first parameter is the name of the related class. Second, since your pivot table doesn't follow the Laravel naming conventions, you need to specify the name of the pivot table in your relationship definition:

public function events()
{
    // first parameter is the name of the related class
    // second parameter is pivot table name
    return $this->belongsToMany(Event::class, 'codes');
}

With this setup, you can do:

// get an order
$order = Order::first();

// has all the events related to an order
$events = $order->events;