How does a Singleton in PHP differ from static classes?

A Singleton in PHP is a design pattern that restricts the instantiation of a class to a single instance. This means that only one instance of the class can exist at any given time. On the other hand, a static class in PHP is a class that contains only static methods and properties, and cannot be instantiated. 

class Singleton {
    private static $instance;

    private function __construct() {
        // private constructor to prevent instantiation
    }

    public static function getInstance() {
        if (self::$instance === null) {
            self::$instance = new self();
        }
        return self::$instance;
    }
}

$instance1 = Singleton::getInstance();
$instance2 = Singleton::getInstance();

var_dump($instance1 === $instance2); // true

Keywords

Singleton static classes PHP design pattern object-oriented programming

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