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ReflectionClass::getAttributes

(PHP 8)

ReflectionClass::getAttributesGets Attributes

Descrição

public ReflectionClass::getAttributes(?string $name = null, int $flags = 0): array

Returns all attributes declared on this class as an array of ReflectionAttribute.

Parâmetros

name

Filtra os resultados para incluir apenas instâncias de ReflectionAttribute para atributos correspondentes a este nome de classe.

flags

Flags para determinar como filtrar os resultados, se name for fornecido.

O padrão é 0, que retornará apenas os resultados para atributos que são da classe name.

A única outra opção disponível é usar ReflectionAttribute::IS_INSTANCEOF, que usará instanceof para filtragem.

Valor Retornado

Array of attributes, as a ReflectionAttribute object.

Exemplos

Exemplo #1 Basic usage

<?php
#[Attribute]
class
Fruit {
}

#[
Attribute]
class
Red {
}

#[
Fruit]
#[
Red]
class
Apple {
}

$class = new ReflectionClass('Apple');
$attributes = $class->getAttributes();
print_r(array_map(fn($attribute) => $attribute->getName(), $attributes));
?>

O exemplo acima produzirá:

Array
(
    [0] => Fruit
    [1] => Red
)

Exemplo #2 Filtering results by class name

<?php
#[Attribute]
class
Fruit {
}

#[
Attribute]
class
Red {
}

#[
Fruit]
#[
Red]
class
Apple {
}

$class = new ReflectionClass('Apple');
$attributes = $class->getAttributes('Fruit');
print_r(array_map(fn($attribute) => $attribute->getName(), $attributes));
?>

O exemplo acima produzirá:

Array
(
    [0] => Fruit
)

Exemplo #3 Filtering results by class name, with inheritance

<?php
interface Color {
}

#[
Attribute]
class
Fruit {
}

#[
Attribute]
class
Red implements Color {
}

#[
Fruit]
#[
Red]
class
Apple {
}

$class = new ReflectionClass('Apple');
$attributes = $class->getAttributes(Color::class, ReflectionAttribute::IS_INSTANCEOF);
print_r(array_map(fn($attribute) => $attribute->getName(), $attributes));
?>

O exemplo acima produzirá:

Array
(
    [0] => Red
)

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User Contributed Notes 2 notes

up
4
sandrenyl at gmail dot com
2 years ago
When using the method getAttributes() to fetch attributes based on a parent class, the proper flag constant is ReflectionAttribute::IS_INSTANCEOF (which equals 2 as mentionned by sergiolibe).

<?php
$reflectionClass
->getAttributes(SomeParentAttribute::class, ReflectionAttribute::IS_INSTANCEOF);
?>
up
3
sergiolibe at gmail dot com
2 years ago
When using getAttributes() with specific attribute class and flags, flag 0 will return just matching attributes with specified class, and 2 will return matching attributes with specified class and children of that class:
<?php
#[Attribute(\Attribute::TARGET_CLASS)]
class
SomeAttribute {}

#[
Attribute(\Attribute::TARGET_CLASS)]
class
ChildAttribute extends SomeAttribute {}

#[
SomeAttribute]
#[
SomeChildAttribute]
class
SomeClass {}

$rc = new ReflectionClass(SomeClass::class);

$r_atts = $rc->getAttributes(SomeAttribute::class, 0); // 0 is default, just given class
echo json_encode(array_map(fn(ReflectionAttribute $r_att) => $r_att->getName(), $r_atts)), PHP_EOL;

$r_atts = $rc->getAttributes(SomeAttribute::class, 2); // given class and children classes
echo json_encode(array_map(fn(ReflectionAttribute $r_att) => $r_att->getName(), $r_atts)), PHP_EOL;
?>

output:
["SomeAttribute"]
["SomeAttribute","ChildAttribute"]
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