如何使用 json 编码从 mysql 数据库获取数据(Symfony 4)?

How can I get data from mysql database with json encode (Symfony 4)?

现在我正在通过 Doctrine 从数据库中获取数据:

$articles = $this->getDoctrine()->getRepository(Article::class)->findAll();
return $this->render('homepage.html.twig', array('articles' => $articles));

这工作正常。但我需要的是通过 json 编码获取数据,因为我想使用服务器端处理数据表。所以我尝试使用 Serializer

  $encoders = array(new XmlEncoder(), new JsonEncoder());
  $normalizers = array(new ObjectNormalizer());

  $serializer = new Serializer($normalizers, $encoders);
  $articles = $this->getDoctrine()->getRepository(Article::class)->findAll();
  $jsonContent = $serializer->serialize($articles, 'json');

  return $this->render('homepage.html.twig', $jsonContent);

但我收到错误消息:

Argument 2 passed to Symfony\Bundle\FrameworkBundle\Controller\AbstractController::render() must be of the type array, string given, called in /Users/work/project/src/Controller/ArticleController.php on line 46 Uncaught PHP Exception Symfony\Component\Debug\Exception\FatalThrowableError: "Argument 2 passed to Symfony\Bundle\FrameworkBundle\Controller\AbstractController::render() must be of the type array, string given, called in /Users/work/project/src/Controller/ArticleController.php on line 46" at /Users/work/project/vendor/symfony/framework-bundle/Controller/ControllerTrait.php line 219

所以将 render 的第二个参数设为一个数组:

return $this->render('homepage.html.twig', ['json_content' => $jsonContent]);

在模板中:

{{ json_content }}

虽然我不知道你为什么要使用模板,因为有一个 json() 方法 returns single json:

return $this->json($articles); // without using serializer