I have some relations:

public function handleServices(array $services): bool
    {
        $allServicesId = $this->services()->get(['service_id'])->pluck('service_id')->toArray();
        return ManyToManyHelper::manageRelations($this->services(), $allServicesId, $services);
    }

There I use ManyToManyHelper

class ManyToManyHelper
{
    public static function manageRelations(BelongsToMany $relation, array $allIds, array $manageIds): bool
    {
        try {
            foreach ($manageIds as $categoryId) {
                if (!in_array($categoryId, $allIds)) {
                    $relation->attach($categoryId);
                }
            }

            $toDeleteIds = array_diff($allIds, $manageIds);
            if (count($toDeleteIds) > 0) {
                $relation->detach($toDeleteIds);
            }
            return true;

        } catch (Exception $exception) {
            return false;
        }
    }
}

But I try to use Syncing Associations - https://laravel.com/docs/9.x/eloquent-relationships#syncing-associations

And I don't understand at all how to change Many to Many to sync.

Can I get any example?

I have one example (https://www.scratchcode.io/source-books/laravel-sync-with-an-example/) but It doesn't give me success

CodePudding user response：

You can do:

public function handleServices(array $services): bool {
    $this->services()->sync($services); 
    return true;
}

This will ensure that all ids listed in $services and only those ids are associated with $this model's services relationship. This is assuming that $this is a model and $services has the list of ids that you want to strictly associate.

CodePudding user response：

Though your question isn't clear, what about this?

         foreach ($manageIds as $categoryId) {
            $toDeleteIds = array_diff($allIds, $manageIds);
            if (count($toDeleteIds) > 0) {
                $relation->detach($toDeleteIds);
            }
            if (!in_array($categoryId, $allIds)) {
                    $relation->sync($categoryId);
            }
         }