The PropertyAccess Component ¶

// ...
$person = new Person();
$person->firstName = 'Wouter';

var_dump($propertyAccessor->getValue($person, 'firstName')); // 'Wouter'

$child = new Person();
$child->firstName = 'Bar';
$person->children = [$child];

var_dump($propertyAccessor->getValue($person, 'children[0].firstName')); // 'Bar'

// ...
class Person
{
    private $firstName = 'Wouter';

    public function getFirstName()
    {
        return $this->firstName;
    }
}

$person = new Person();

var_dump($propertyAccessor->getValue($person, 'first_name')); // 'Wouter'

// ...
class Person
{
    private $author = true;
    private $children = [];

    public function isAuthor()
    {
        return $this->author;
    }

    public function hasChildren()
    {
        return 0 !== count($this->children);
    }
}

$person = new Person();

if ($propertyAccessor->getValue($person, 'author')) {
    var_dump('This person is an author');
}
if ($propertyAccessor->getValue($person, 'children')) {
    var_dump('This person has children');
}

// ...
class Person
{
    public $name;
}

$person = new Person();

$propertyAccessor = PropertyAccess::createPropertyAccessorBuilder()
    ->disableExceptionOnInvalidPropertyPath()
    ->getPropertyAccessor();

// instead of throwing an exception the following code returns null
$value = $propertyAccessor->getValue($person, 'birthday');

class Person
{
}

class Comment
{
    public ?Person $person = null;
    public string $message;
}

$comment = new Comment();
$comment->message = 'test';

// This code throws an exception of type
// Symfony\Component\PropertyAccess\Exception\UnexpectedTypeException
var_dump($propertyAccessor->getValue($comment, 'person.firstname'));

// If a property marked with the nullsafe operator is null, the expression is
// no longer evaluated and null is returned immediately without throwing an exception
var_dump($propertyAccessor->getValue($comment, 'person?.firstname')); // null

// ...
class Person
{
    private $children = [
        'Wouter' => [...],
    ];

    public function __get($id)
    {
        return $this->children[$id];
    }
}

$person = new Person();

var_dump($propertyAccessor->getValue($person, 'Wouter')); // [...]

// ...
class Person
{
    private $children = [
        'wouter' => [...],
    ];

    public function __call($name, $args)
    {
        $property = lcfirst(substr($name, 3));
        if ('get' === substr($name, 0, 3)) {
            return $this->children[$property] ?? null;
        } elseif ('set' === substr($name, 0, 3)) {
            $value = 1 == count($args) ? $args[0] : null;
            $this->children[$property] = $value;
        }
    }
}

$person = new Person();

// enables PHP __call() magic method
$propertyAccessor = PropertyAccess::createPropertyAccessorBuilder()
    ->enableMagicCall()
    ->getPropertyAccessor();

var_dump($propertyAccessor->getValue($person, 'wouter')); // [...]

// ...
class Person
{
    /**
     * @var string[]
     */
    private $children = [];

    public function getChildren(): array
    {
        return $this->children;
    }

    public function addChild(string $name): void
    {
        $this->children[$name] = $name;
    }

    public function removeChild(string $name): void
    {
        unset($this->children[$name]);
    }
}

$person = new Person();
$propertyAccessor->setValue($person, 'children', ['kevin', 'wouter']);

var_dump($person->getChildren()); // ['kevin', 'wouter']

// ...
class PeopleList
{
    // ...

    public function joinPeople(string $people): void
    {
        $this->peoples[] = $people;
    }

    public function leavePeople(string $people): void
    {
        foreach ($this->peoples as $id => $item) {
            if ($people === $item) {
                unset($this->peoples[$id]);
                break;
            }
        }
    }
}

use Symfony\Component\PropertyInfo\Extractor\ReflectionExtractor;
use Symfony\Component\PropertyAccess\PropertyAccessor;

$list = new PeopleList();
$reflectionExtractor = new ReflectionExtractor(null, null, ['join', 'leave']);
$propertyAccessor = new PropertyAccessor(PropertyAccessor::DISALLOW_MAGIC_METHODS, PropertyAccessor::THROW_ON_INVALID_PROPERTY_PATH, null, $reflectionExtractor, $reflectionExtractor);
$propertyAccessor->setValue($person, 'peoples', ['kevin', 'wouter']);

var_dump($person->getPeoples()); // ['kevin', 'wouter']

// ...
$propertyAccessorBuilder = PropertyAccess::createPropertyAccessorBuilder();

$propertyAccessorBuilder->enableMagicCall(); // enables magic __call
$propertyAccessorBuilder->enableMagicGet(); // enables magic __get
$propertyAccessorBuilder->enableMagicSet(); // enables magic __set
$propertyAccessorBuilder->enableMagicMethods(); // enables magic __get, __set and __call

$propertyAccessorBuilder->disableMagicCall(); // disables magic __call
$propertyAccessorBuilder->disableMagicGet(); // disables magic __get
$propertyAccessorBuilder->disableMagicSet(); // disables magic __set
$propertyAccessorBuilder->disableMagicMethods(); // disables magic __get, __set and __call

// checks if magic __call, __get or __set handling are enabled
$propertyAccessorBuilder->isMagicCallEnabled(); // true or false
$propertyAccessorBuilder->isMagicGetEnabled(); // true or false
$propertyAccessorBuilder->isMagicSetEnabled(); // true or false

// At the end get the configured property accessor
$propertyAccessor = $propertyAccessorBuilder->getPropertyAccessor();

// Or all in one
$propertyAccessor = PropertyAccess::createPropertyAccessorBuilder()
    ->enableMagicCall()
    ->getPropertyAccessor();

// enable handling of magic __call, __set but not __get:
$propertyAccessor = new PropertyAccessor(PropertyAccessor::MAGIC_CALL | PropertyAccessor::MAGIC_SET);