The SplObserver interface

- « SeekableIterator::seek

- SplObserver::update »

- PHP Manual
- Interfaces
- The SplObserver interface

# The SplObserver interface

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

## Introduction

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

- SplObserver::update — Receive update from subject