PHP: Liste de valeurs

Liste de valeurs

Les Enums pures et les Enums avec valeur de base implémentent toute deux une interface interne nommée UnitEnum. UnitEnum comprend une méthode statique cases(). cases() renvoie un tableau compact de tous les cas définis dans l'ordre de leur déclaration.

<?php

Suit::cases();
// Produces: [Suit::Hearts, Suit::Diamonds, Suit::Clubs, Suit::Spades]
?>

La définition manuelle d'une méthode cases() sur un Enum entraînera une erreur fatale.

Found A Problem?

Learn How To Improve This Page • Submit a Pull Request • Report a Bug

＋add a note

User Contributed Notes 2 notes

down

theking2 at king dot ma ¶

2 years ago

As ::cases() creates a Iteratable it is possible to use it in a foreach loop. In combination with value backed enum this can result in very compact and very readable code:

<?php
/** Content Security Policy directives */
enum CspDirective: String {
  case Default = "default-src";
  case Image = "img-src";
  case Font = "font-src";
  case Script = "script-src";
  case Style = "style-src";
}

/** list all CSP directives */
foreach( CspSource::cases() as $directive ) {
  echo $directive-> value . PHP_EOL;
}
?>
Which results in:
default-src
img-src
font-src
script-src
style-src

down

anhaia dot gabriel at gmail dot com ¶

3 months ago

If you want to get all the values of the Enum in a list of `string`, you might do something like this:

<?php

enum MyEnum: string
{
    case OPTION_A = 'option_a';
    case OPTION_B = 'option_b';
    case OPTION_C = 'option_c';

    public static function values(): array
    {
        return array_map(fn ($case) => $case->value, self::cases());
    }
}

?>

＋add a note