Question

我遇到此查询的问题。我想只获得带有属性$ categoria的汽车，我这样做：

public function listcategoriaAction($categoria)
    {
        $posts = $this->get('doctrine')->getManager()->createQueryBuilder()->select('p')->from('CarsCarsBundle:Post',  'p')->where('p.categoria = :categoria')->setParameter('categoria', $categoria)->getQuery()->getResult();

        return $this->render('CarsCarsBundle:Cars:list.html.twig', array('posts' => $posts));
    }

但我收到的是一个空数组。任何提示将不胜感激

Answer 1

首先，我假设此代码在控制器中。我强烈建议您避免在控制器上添加查询，而是use repositories。

我认为发生此错误是因为您之前未通过参数收到类别ID。这样就可以了：

$dm = $this->get('doctrine')->getManager();

//This gets the object from db
$category = $dm->getRepository('CarsCarsBundle:Category')->findOneById($categoria);

if ($category !== null) {

    $posts = $dm->getRepository('CarsCarsBundle:Post')->findOneByCategory($category);

} else {

    //The id received is not on the db.
}

教义问题与何处

1 个答案: