BackedEnum::tryFrom
(PHP 8 >= 8.1.0)
BackedEnum::tryFrom — Maps a scalar to an enum instance or null
Beschreibung
$value
): ?staticThe tryFrom() method translates a string or int into the corresponding Enum case, if any. If there is no matching case defined, it will return null.
Parameter-Liste
-
value
-
The scalar value to map to an enum case.
Rückgabewerte
A case instance of this enumeration, or null if not found.
Beispiele
Beispiel #1 Basic usage
The following example illustrates how enum cases are returned.
<?php
enum Suit: string
{
case Hearts = 'H';
case Diamonds = 'D';
case Clubs = 'C';
case Spades = 'S';
}
$h = Suit::tryFrom('H');
var_dump($h);
$b = Suit::tryFrom('B') ?? Suit::Spades;
var_dump($b);
?>
Das oben gezeigte Beispiel erzeugt folgende Ausgabe:
enum(Suit::Hearts) enum(Suit::Spades)
Siehe auch
- UnitEnum::cases() - Generates a list of cases on an enum
- BackedEnum::from() - Maps a scalar to an enum instance