Laravel同步无法使用空数组

Question

I've a method looks like this:

public function saveContacts(Request $request)
{
    if($request->contacts) {
        $contacts = collect($request->contacts)->pluck('id');
        $this->contacts()->sync($contacts->toArray());
    }
}

It's working but if $request->contacts is an empty array it does not remove all records. What could be the case here?

Answer 1

You can do this:

if ($request->contacts) {
    $contacts = collect($request->contacts)->pluck('id')->toArray();
    if (empty($contacts)) {
        $this->contacts()->detach();
    } else {
        $this->contacts()->sync($contacts);
    }
}