The ArrayAccess interface

- « Throwable::__toString

- ArrayAccess::offsetExists »

- PHP Manual
- Predefined Interfaces and Classes
- The ArrayAccess interface

# The ArrayAccess interface

(PHP 5, PHP 7, PHP 8)

## Introduction

Interface to provide accessing objects as arrays.

## Interface synopsis

interface ArrayAccess {
/* Methods */
public offsetExists(mixed `$offset`): bool
public offsetGet(mixed `$offset`): mixed
public offsetSet(mixed `$offset`, mixed `$value`): void
public offsetUnset(mixed `$offset`): void
}

Example #1 Basic usage

    <?phpclass Obj implements ArrayAccess {    public $container = [        "one"   => 1,        "two"   => 2,        "three" => 3,    ];    public function offsetSet($offset, $value): void {        if (is_null($offset)) {            $this->container[] = $value;        } else {            $this->container[$offset] = $value;        }    }    public function offsetExists($offset): bool {        return isset($this->container[$offset]);    }    public function offsetUnset($offset): void {        unset($this->container[$offset]);    }    public function offsetGet($offset): mixed {        return isset($this->container[$offset]) ? $this->container[$offset] : null;    }}$obj = new Obj;var_dump(isset($obj["two"]));var_dump($obj["two"]);unset($obj["two"]);var_dump(isset($obj["two"]));$obj["two"] = "A value";var_dump($obj["two"]);$obj[] = 'Append 1';$obj[] = 'Append 2';$obj[] = 'Append 3';print_r($obj);?>

The above example will output something similar to:

    bool(true)
    int(2)
    bool(false)
    string(7) "A value"
    obj Object
    (
        [container:obj:private] => Array
            (
                [one] => 1
                [three] => 3
                [two] => A value
                [0] => Append 1
                [1] => Append 2
                [2] => Append 3
            )

    )

## Table of Contents

- ArrayAccess::offsetExists — Whether an offset exists
- ArrayAccess::offsetGet — Offset to retrieve
- ArrayAccess::offsetSet — Assign a value to the specified offset
- ArrayAccess::offsetUnset — Unset an offset