Sohel Rana sohelrana820

Why objects (usually) use less memory than arrays in PHP

This is just a small post in response to [this tweet][tweet] by Julien Pauli (who by the way is the release manager for PHP 5.5). In the tweet he claims that objects use more memory than arrays in PHP. Even though it can be like that, it's not true in most cases. (Note: This only applies to PHP 5.4 or newer.)

The reason why it's easy to assume that objects are larger than arrays is because objects can be seen as an array of properties and a bit of additional information (like the class it belongs to). And as array + additional info > array it obviously follows that objects are larger. The thing is that in most cases PHP can optimize the array part of it away. So how does that work?

The key here is that objects usually have a predefined set of keys, whereas arrays don't:

	<?php
	/**
	* @Author Shaharia Azam
	* @Author URL http://www.shahariaazam.com
	*
	* @Description this function will make a .zip folder by adding multiple files.
	* @link http://php.net/manual/en/book.zip.php
	*
	* @param array $SourceFiles
	* @param string $ZipDestination

	<?php
	public function Batch($BatchNo){
	if($BatchNo==1){
	return "First Batch";
	}
	else if($BatchNo==2){
	return "Second Batch";
	}
	else if($BatchNo==3){
	return "Third Batch";

	<!DOCTYPE html>
	<html>
	<head>
	<title>LESS Practice</title>
	<link rel="stylesheet/less" type="text/css" href="styles.less" />
	<script src="less.js" type="text/javascript"></script>
	</head>
	<body>
	<h2 class="h2">Hello World</h2>
	</body>

	<?php
	$MyArray = array('Name'=>'Rana','ID'=>'092-15-820','Batch'=>'23');
	// If you want to echo the name just write "echo $MyArray['Name']";
	echo $MyArray['Name'];


	//Another way
	$MyArray2 = array('Rana','092-15-820','23');
	// If you want to echo the name just write "echo $MyArray2[0]";
	echo $MyArray2[0];

	<?php
	/**
	* @Author: Sohel Rana
	* @URI : http://www.sohelranabd.com
	* @Description: This is simple example of PHP auto loading class
	*/

	class MyClass // Creating First Class
	{
	public function getValue(){

	jQuery(function($) {
	$('form[data-async]').live('submit', function(event) {
	var $form = $(this);
	var $target = $($form.attr('data-target'));

	$.ajax({
	type: $form.attr('method'),
	url: $form.attr('action'),
	data: $form.serialize(),

	public function imgValidate()
	{
	$validateImg = array(
	'image' => array(
	'isImage' => array(
	'rule' => array('isImage'),
	'message' => 'Please provide an image!',
	),
	'dimension' => array(
	'rule' => array('dimension', 320, 100),

	public function uploadImage($filename, $document, $path)
	{
	$ext = $this->Img->ext($document['name']);
	$origFile = $filename. '.'. $ext;
	$targetDir = WWW_ROOT . $path;
	$upload = $this->Img->upload($document['tmp_name'], $targetDir, $origFile);
	if ($upload == 'Success') {
	return 'category/'.$origFile;
	}
	return false;