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The SplObserver interface

Introduction

(PHP 5 >= 5.1.0, PHP 7, PHP 8)

The SplObserver interface is used alongside SplSubject to implement the Observer Design Pattern.

Interface synopsis

interface SplObserver {
/* Methods */
public update(SplSubject $subject): void
}

Table of Contents

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Licensed under the Creative Commons Attribution License v3.0 or later.
https://www.php.net/manual/en/class.splobserver.php