Doctrine\ODM\MongoDB\PersistentCollection::containsKey PHP Method

    public function containsKey($key)
    {
        $this->initialize();
        return $this->coll->containsKey($key);
    }

 /**
  * {@inheritdoc}
  */
 public function containsKey($key)
 {
     return $this->collection->containsKey($key);
 }