Become Zend Certified

Prepare for the ZCE exam using our quizzes (web or iPad/iPhone). More info...

When you're ready get 7.5% off your exam voucher using voucher CJQNOV23 at the Zend Store

The RecursiveCallbackFilterIterator class

(PHP 5 >= 5.4.0)


Class synopsis

RecursiveCallbackFilterIterator extends CallbackFilterIterator implements OuterIterator , RecursiveIterator {
/* Methods */
public __construct ( RecursiveIterator $iterator , string $callback )
public RecursiveCallbackFilterIterator getChildren ( void )
public void hasChildren ( void )
/* Inherited methods */
public string CallbackFilterIterator::accept ( void )


The callback should accept up to three arguments: the current item, the current key and the iterator, respectively.

Example #1 Available callback arguments


 * Callback for RecursiveCallbackFilterIterator
 * @param $current   Current item's value
 * @param $key       Current item's key
 * @param $iterator  Iterator being filtered
 * @return boolean   TRUE to accept the current item, FALSE otherwise
function my_callback($current$key$iterator) {
// Your filtering code here


Filtering a recursive iterator generally involves two conditions. The first is that, to allow recursion, the callback function should return TRUE if the current iterator item has children. The second is the normal filter condition, such as a file size or extension check as in the example below.

Example #2 Recursive callback basic example


= new RecursiveDirectoryIterator(__DIR__);

// Filter large files ( > 100MB)
$files = new RecursiveCallbackFilterIterator($dir, function ($current$key$iterator) {
// Allow recursion
if ($iterator->hasChildren()) {
// Check for large file
if ($current->isFile() && $current->getSize() > 104857600) {
foreach (new 
RecursiveIteratorIterator($files) as $file) {
$file->getPathname() . PHP_EOL;


Table of Contents

PHP Manual