DirectoryIterator::__construct

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.

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

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/<?phpclass 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>';?>

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.

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...

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.}

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 />";    } }?>

udvig dot ericson at gmail dot com29-Jul-2006 07:48In 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";}?>

We can now replace the old fashioned way of listing the content from a directory!the old way:<?phpif ($handle = opendir('/home/fernando/temp')) {    while (false !== ($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();}?>