枢轴列在模型Laravel中隐藏

Question

I have Post model with relation:

public function prices() {
    return $this->morphedByMany('App\Price', 'postable');
}

I have a separate table postables with columns:

- postable_id
- postable_type
- custom (type: json)

Why when I want do: $post->pivot->custom I get null, why? When I do dd($post) column custom not found in collection.

Answer 1

You have to specify the custom attributes when you define the relation, like this:

public function prices() {
    return $this->morphedByMany('App\Price', 'postable')->withPivot('custom');
}

If you want to cast the custom attribute, you would have to create a model for the pivot table, like this:

use Illuminate\Database\Eloquent\Relations\Pivot;

class Postable extends Pivot
{
    protected $casts = [
        'custom' => 'array',
    ];
}

Reference this model in your relation definition:

return $this->morphedByMany('App\Price', 'postable')
    ->using('App\Postable')
    ->withPivot('custom');

Now you can retrieve the value like this:

foreach ($post->prices as $price) {
    echo $price->pivot->custom;
}