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Serialization

Serialization

Enumerations are serialized differently from objects. Specifically, they have a new serialization code, , that specifies the name of the enum case. The deserialization routine is then able to use that to set a variable to the existing singleton value. That ensures that: "E"

<?php

Suit::Hearts === unserialize(serialize(Suit::Hearts));

print serialize(Suit::Hearts);
// E:11:"Suit:Hearts";
?>

On deserialization, if an enum and case cannot be found to match a serialized value a warning will be issued and false returned.

If a Pure Enum is serialized to JSON, an error will be thrown. If a Backed Enum is serialized to JSON, it will be represented by its scalar value only, in the appropriate type. The behavior of both may be overridden by implementing . JsonSerializable

For , the output of an enum case is slightly different from objects to minimize confusion. print_r

<?php

enum Foo {
    case Bar;
}

enum Baz: int {
    case Beep = 5;
}

print_r(Foo::Bar);
print_r(Baz::Beep);

/* Produces

Foo Enum (
    [name] => Bar
)
Baz Enum:int {
    [name] => Beep
    [value] => 5
}
*/
?>
Vorige ← Value listing Volgende Why enums aren't extendable →

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