How does symfony convert data read from findall to json?

How does symfony convert data read from findall to json?

$repository = $this->getDoctrine()->getRepository('AppBundle:User');$all = $repository->findAll();

array (size=2)  0 =>     object(AppBundle\Entity\User)[248]      private 'id' => int 1      private 'name' => string 'A Foo Bar' (length=9)      private 'pass' => string '19.99' (length=5)  1 =>     object(AppBundle\Entity\User)[251]      private 'id' => int 2      private 'name' => string 'Two Fot Bar' (length=11)      private 'pass' => string '40.00' (length=5)

The returned data is like this. how can we convert it to json data?
I now use return new JsonResponse ($ all); [{}]

Reply to discussion (solution)

You need to implement the JsonSerializable interface for AppBundle \ Entity \ User
For example

class T implements JsonSerializable {  private $id;  private $name;  private $pass;  function __construct($id, $name, $pass) {    $this->id = $id;    $this->name = $name;    $this->pass = $pass;  }  function jsonSerialize() {    return array(      'id' => $this->id,      'name' => $this->name,      'pass' => $this->pass,      );  }}$d[] = new T(1, 'a', 'p');$d[] = new T(2, 'b', 'p');echo json_encode($d);

[{"Id": 1, "name": "a", "pass": "p" },{ "id": 2, "name": "B ", "pass": "p"}]
Otherwise, it can only be [{}, {}]
Because the returned property is private

You need to implement the JsonSerializable interface for AppBundle \ Entity \ User
For example

class T implements JsonSerializable {  private $id;  private $name;  private $pass;  function __construct($id, $name, $pass) {    $this->id = $id;    $this->name = $name;    $this->pass = $pass;  }  function jsonSerialize() {    return array(      'id' => $this->id,      'name' => $this->name,      'pass' => $this->pass,      );  }}$d[] = new T(1, 'a', 'p');$d[] = new T(2, 'b', 'p');echo json_encode($d);

[{"Id": 1, "name": "a", "pass": "p" },{ "id": 2, "name": "B ", "pass": "p"}]
Otherwise, it can only be [{}, {}]
Because the returned property is private

Thanks, because the property is private.