Symfony 怎么把序列化对象转为数组

Serializer

normalize

Symfony\Component\Serializer\Serializer

Normalizer

Encoder

Normalizer

Encoder

Normalizer

use Symfony\Component\Serializer\Encoder\JsonEncoder;
use Symfony\Component\Serializer\Normalizer\ObjectNormalizer;
use Symfony\Component\Serializer\Serializer;
use App\Entity\YourEntity; // 假设这是你要序列化的实体类

// 1. 准备Normalizer和Encoder
// ObjectNormalizer是把对象属性转换成数组的关键
$normalizers = [new ObjectNormalizer()];
// JsonEncoder在这里不是必须的，但如果需要先转JSON再转数组，它就有用了
$encoders = [new JsonEncoder()];

// 2. 实例化Serializer
$serializer = new Serializer($normalizers, $encoders);

// 3. 假设你有一个实体对象
$entity = new YourEntity();
$entity->setId(1);
$entity->setName('示例名称');
$entity->setDescription('这是一段描述。');
// 假设实体里还有个DateTime对象
$entity->setCreatedAt(new \DateTimeImmutable());

// 4. 使用normalize方法将对象转换为数组
// 传入对象和目标格式（'array'）
$dataArray = $serializer->normalize($entity, 'array');

// $dataArray 现在就是一个包含了对象属性的关联数组
// 比如：
/*
[
    'id' => 1,
    'name' => '示例名称',
    'description' => '这是一段描述。',
    'createdAt' => '2023-10-27T10:00:00+00:00' // 默认会是ISO 8601格式
]
*/

// 如果你想控制哪些属性被序列化，或者改变属性名，可以利用上下文（Context）
// 比如，只序列化 'id' 和 'name' 属性：
$context = [
    ObjectNormalizer::ATTRIBUTES => ['id', 'name']
];
$limitedDataArray = $serializer->normalize($entity, 'array', $context);
/*
[
    'id' => 1,
    'name' => '示例名称'
]
*/

// 在Symfony应用中，通常你会通过依赖注入来获取Serializer服务，而不是手动实例化：
/*
// 在你的Controller或Service中
use Symfony\Component\Serializer\SerializerInterface;

class MyService
{
    private $serializer;

    public function __construct(SerializerInterface $serializer)
    {
        $this->serializer = $serializer;
    }

    public function processEntity(YourEntity $entity): array
    {
        // 这里可以直接使用注入的serializer
        return $this->serializer->normalize($entity, 'array');
    }
}
*/

User

posts

Post

author

User

User

posts

Post

author

author

posts

#[Groups("group_name")]

// src/Entity/User.php
use Symfony\Component\Serializer\Annotation\Groups;

class User
{
    #[Groups(['user:read', 'post:read'])]
    private $id;

    #[Groups(['user:read', 'post:read'])]
    private $name;

    // 当从User的角度读取时，我可能只想要Post的ID和标题，而不是整个Post对象
    #[Groups(['user:read'])]
    private $posts; // Collection of Post objects
}

// src/Entity/Post.php
use Symfony\Component\Serializer\Annotation\Groups;

class Post
{
    #[Groups(['post:read', 'user:read'])]
    private $id;

    #[Groups(['post:read', 'user:read'])]
    private $title;

    // 当从Post的角度读取时，我可能只想要User的ID和名称，避免循环
    #[Groups(['post:read'])]
    private $author; // User object
}

$user = /* ... 获取User对象 ... */;
$data = $serializer->normalize($user, 'array', ['groups' => ['user:read']]);
// 此时，User对象会包含其id、name，以及其关联的posts（但posts内部的author属性会被忽略，因为它不在post:read组中或没有特别配置）

ObjectNormalizer

ObjectNormalizer::ENABLE_MAX_DEPTH

use Symfony\Component\Serializer\Normalizer\ObjectNormalizer;

$normalizers = [new ObjectNormalizer(null, null, null, null, null, null, [
    ObjectNormalizer::CIRCULAR_REFERENCE_HANDLER => function ($object, $format, $context) {
        // 比如，只返回ID
        return $object->getId();
    },
])];
$serializer = new Serializer($normalizers, [new JsonEncoder()]); // 即使是转数组，也需要Encoder，因为Normalizer内部可能会用到

circular_reference_handler

#[Groups]

max_depth

max_depth

NormalizerInterface

DenormalizerInterface

supportsNormalization()

normalize()

DateTimeInterface

// src/Serializer/Normalizer/TimestampNormalizer.php
namespace App\Serializer\Normalizer;

use Symfony\Component\Serializer\Normalizer\NormalizerInterface;
use DateTimeInterface;

class TimestampNormalizer implements NormalizerInterface
{
    public function normalize($object, string $format = null, array $context = []): array|string|int|float|bool|\ArrayObject|null
    {
        // 确保你的DateTime对象是可被序列化的，这里直接返回时间戳
        return $object->getTimestamp();
    }

    public function supportsNormalization($data, string $format = null, array $context = []): bool
    {
        // 只有当数据是DateTimeInterface的实例时，才使用这个Normalizer
        return $data instanceof DateTimeInterface;
    }

    public function getSupportedTypes(?string $format): array
    {
        // 声明这个Normalizer支持的类型
        return [
            DateTimeInterface::class => true,
        ];
    }
}

ObjectNormalizer

ObjectNormalizer

DateTime

# config/services.yaml
services:
    App\Serializer\Normalizer\TimestampNormalizer:
        tags: ['serializer.normalizer'] # 标记为序列化器服务

#[SerializedName]

serializer.denormalization

serializer.normalization

User

admin:read

public:read

// 对于管理员接口
#[Route('/api/admin/users/{id}', methods: ['GET'])]
public function getUserForAdmin(User $user, SerializerInterface $serializer): JsonResponse
{
    $data = $serializer->normalize($user, 'json', ['groups' => ['user:read', 'user:admin_details']]);
    return new JsonResponse($data);
}

// 对于公共接口
#[Route('/api/public/users/{id}', methods: ['GET'])]
public function getUserForPublic(User $user, SerializerInterface $serializer): JsonResponse
{
    $data = $serializer->normalize($user, 'json', ['groups' => ['user:read']]);
    return new JsonResponse($data);
}

User

#[MaxDepth]

// src/Entity/User.php
use Symfony\Component\Serializer\Annotation\MaxDepth;

class User
{
    // ...
    #[MaxDepth(1)] // 只序列化一层Post的信息，避免深层嵌套
    private $posts;
}

#[Groups]

user:v1:read

user:v2:read

if/else