DirectoryIterator::__construct

(PHP 5, PHP 7, PHP 8)

DirectoryIterator::__constructConstructs a new directory iterator from a path

Description

public DirectoryIterator::__construct(string $directory)

Constructs a new directory iterator from a path.

Parameters

directory

The path of the directory to traverse.

Errors/Exceptions

Throws an UnexpectedValueException if the directory does not exist.

Throws a ValueError if the directory is an empty string.

Changelog

Version Description
8.0.0 Now throws a ValueError if directory is an empty string; previously it threw a RuntimeException.

Examples

Example #1 A DirectoryIterator::__construct() example

This example will list the contents of the directory containing the script.

<?php
$dir
= new DirectoryIterator(dirname(__FILE__));
foreach (
$dir as $fileinfo) {
if (!
$fileinfo->isDot()) {
var_dump($fileinfo->getFilename());
}
}
?>

add a note

User Contributed Notes 9 notes

up
8
kendsnyder at gmail dot com
15 years ago
Don't store DirectoryIterator objects for later; you will get an error saying "too many open files" when you store more than the operating system limit (usually 256 or 1024).

For example, this will yield an error if the directory has too many files:

<?php
$files
= array();
foreach (new
DirectoryIterator('myDir') as $file) {
$files[] = $file;
}
?>

Presumably, this approach is memory intensive as well.
up
10
a dot lyskawa at nisza dot org
14 years ago
Here's all-in-one DirectoryIterator:

<?php

/**
* Real Recursive Directory Iterator
*/
class RRDI extends RecursiveIteratorIterator {
/**
* Creates Real Recursive Directory Iterator
* @param string $path
* @param int $flags
* @return DirectoryIterator
*/
public function __construct($path, $flags = 0) {
parent::__construct(new RecursiveDirectoryIterator($path, $flags));
}
}

/**
* Real RecursiveDirectoryIterator Filtered Class
* Returns only those items which filenames match given regex
*/
class AdvancedDirectoryIterator extends FilterIterator {
/**
* Regex storage
* @var string
*/
private $regex;
/**
* Creates new AdvancedDirectoryIterator
* @param string $path, prefix with '-R ' for recursive, postfix with /[wildcards] for matching
* @param int $flags
* @return DirectoryIterator
*/
public function __construct($path, $flags = 0) {
if (
strpos($path, '-R ') === 0) { $recursive = true; $path = substr($path, 3); }
if (
preg_match('~/?([^/]*\*[^/]*)$~', $path, $matches)) { // matched wildcards in filename
$path = substr($path, 0, -strlen($matches[1]) - 1); // strip wildcards part from path
$this->regex = '~^' . str_replace('*', '.*', str_replace('.', '\.', $matches[1])) . '$~'; // convert wildcards to regex
if (!$path) $path = '.'; // if no path given, we assume CWD
}
parent::__construct($recursive ? new RRDI($path, $flags) : new DirectoryIterator($path));
}
/**
* Checks for regex in current filename, or matches all if no regex specified
* @return bool
*/
public function accept() { // FilterIterator method
return $this->regex === null ? true : preg_match($this->regex, $this->getInnerIterator()->getFilename());
}
}

?>

Some examples:

<?php

/* @var $i DirectoryIterator */

foreach (new AdvancedDirectoryIterator('.') as $i) echo $i->getPathname() . '<br/>';
// will output all files and directories in CWD

foreach (new AdvancedDirectoryIterator('-R *.php') as $i) echo $i->getPathname() . '<br/>';
// will output all php files in CWD and all subdirectories

foreach (new AdvancedDirectoryIterator('-R js/jquery-*.js') as $i) echo $i->getPathname() . '<br/>';
// will output all jQuery versions in directory js, or throw an exception if directory js doesn't exist

?>

Pretty cool, huh? :)
up
2
goran at extensionsforjoomla dot com
17 years ago
I needed to match in directory tree file name(s) by regular expression. Code is based on Marcus Börger class DirectoryTreeIterator http://cvs.php.net/viewvc.cgi/php-src/ext/spl/examples/ and on examples given in his lecture Introduction to object oriented PHP at PHP Quebec conference 2007 http://talks.somabo.de/
<?php
class KeyFilter extends FilterIterator
{
private
$_rx;

function
__construct(Iterator $it, $regex)
{
parent::__construct($it);
$this->_rx= $regex;
}

function
accept()
{
return
ereg($this->_rx,$this->getInnerIterator()->key());
}

protected function
__clone() {
return
false;
}
}

class
DirMach extends KeyFilter
{
function
__construct($path , $regex)
{
parent::__construct(
new
DirectoryTreeIterator($path), $regex);
}

function
current()
{
return
parent::key();
}

function
key()
{
return
parent::key();
}
}

class
DirectoryTreeIterator extends RecursiveIteratorIterator
{
/** Construct from a path.
* @param $path directory to iterate
*/
function __construct($path)
{
try {
parent::__construct(
new
RecursiveCachingIterator(
new
RecursiveDirectoryIterator($path, RecursiveDirectoryIterator::KEY_AS_FILENAME
),
CachingIterator::CALL_TOSTRING|CachingIterator::CATCH_GET_CHILD
),
parent::SELF_FIRST
);
} catch(
Exception $e) {
echo
$e->getMessage();
exit;
}
}

/** @return the current element prefixed with ASCII graphics
*/
function current()
{
if (
$this->hasChildren())
$this->next();
return
$this->key();
}

/** Aggregates the inner iterator
*/
function __call($func, $params)
{
return
call_user_func_array(array($this->getSubIterator(), $func), $params);
}
}
$PathToSearch = 'path_to_search';
$regex = 'regular_expression';
$FileList = new DirMach($PathToSearch, $regex);
foreach (
$FileList as $file) {
$match[] = $file;
}
echo
'<pre>';
var_dump($match);
echo
'</pre>';
?>
up
1
ahmad dot mayahi at gmail dot com
4 years ago
Many developers get confused between DirectoryIterator and FilesystemIterator, there are a few small differences that I'm goning to list them here:

DirectoryIterator:
* Includes the "." and ".." within the path.
* Numberd keys.
* Path is not included in in value.
* No configuration available.
* You do need to use "clone" when storing the elements into an array.

Example:
<?php
$files
= [];
foreach (
$dir as $key => $item) {
echo
$key.PHP_EOL; // The key is a number
$files[] = $item;
}

echo
$files[0]->getFilename(); // nothing happens here, you do need to use clone $item inside the foreach

?>

FilesystemIterator:
* Dot files skipped.
* Pathname is used as a key as well as a value.
* Configurable.
* Uses SplFileInfo to store the files.

"FilesystemIterator" it's an enhanced version of DirectoryIterator, and I prefer to use it instead of the DirectoryIterator.
up
0
h.man
3 years ago
RecursiveDirectoryIterator seems to close file handles that are currently open. After using it "PHP Warning: fwrite(): supplied resource is not a valid stream resource in..." is given...
up
0
cmanley at example dot com
5 years ago
Beware that DirectoryIterator returns a reference to itself with each iteration instead of a unique new SplFileInfo object as one may first assume.
This is important to know if you want to push the results of an iteration into an array for later processing.
If you do that, then all entries in the array will be the same DirectoryIterator object with the same internal state (most likely invalid - see the valid() method), which is probably not what you want.
So if you do want to store the iteration results in an array, then you must convert them to either plain strings or new SplFileInfo objects first.

$todo = [];
foreach (new DirectoryIterator('/some/dir') as $entry) {
if (!$entry->isFile()) {
continue;
}
#$todo []= $entry; # Don't do this!
$todo []= new SplFileInfo($entry->getFilename()); # Do this!
#$todo []= $entry->getFilename(); # or do this if you're only interested in the file name.
}
up
0
pcdinh at phpvietnam dot net
17 years ago
I need to traverse recursively through a directory tree and get all sub-directory paths and has written a snippet to do that.

<?php
$path
= "D:\webroot\phpvietnamcms";
foreach (new
RecursiveIteratorIterator(
new
RecursiveDirectoryIterator($path, RecursiveDirectoryIterator::KEY_AS_PATHNAME), RecursiveIteratorIterator::CHILD_FIRST) as $file => $info) {
if (
$info->isDir())
{
echo
$file."<br />";
}
}

?>
up
0
springub at northclick dot de
17 years ago
udvig dot ericson at gmail dot com
29-Jul-2006 07:48

In response to the comment below from udvig. The Example ist wrong, here is the right one:

<?php
$dir
= new DirectoryIterator("/tmp");
foreach (
$dir as $file) {
if (
$file->isDot()) {
continue;
}
echo
$file->getFilename() . "\n";
}
?>
up
0
fernandobassani at gmail dot com
18 years ago
We can now replace the old fashioned way of listing the content from a directory!

the old way:
<?php
if ($handle = opendir('/home/fernando/temp')) {
while (
false !== ($file = readdir($handle))) {
if (
$file != "." && $file != "..") {
print
"$file <br />";
}
}
closedir($handle);
}
?>

the new way:
<?php
$dir
= new DirectoryIterator('/home/fernando/temp');
while(
$dir->valid()) {
if(!
$dir->isDot()) {
print
$dir->current()."<br />";
}
$dir->next();
}
?>
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