[php] List all the files and folders in a Directory with PHP recursive function

I'm trying to go through all of the files in a directory, and if there is a directory, go through all of its files and so on until there are no more directories to go to. Each and every processed item will be added to a results array in the function below. It is not working though I'm not sure what I can do/what I did wrong, but the browser runs insanely slow when this code below is processed, any help is appreciated, thanks!

Code:

    function getDirContents($dir){
        $results = array();
        $files = scandir($dir);

            foreach($files as $key => $value){
                if(!is_dir($dir. DIRECTORY_SEPARATOR .$value)){
                    $results[] = $value;
                } else if(is_dir($dir. DIRECTORY_SEPARATOR .$value)) {
                    $results[] = $value;
                    getDirContents($dir. DIRECTORY_SEPARATOR .$value);
                }
            }
    }

    print_r(getDirContents('/xampp/htdocs/WORK'));

Ready for copy and paste function for common use cases, improved/extended version of one answer above:

function getDirContents(string $dir, int $onlyFiles = 0, string $excludeRegex = '~/\.git/~', int $maxDepth = -1): array {
    $results = [];
    $scanAll = scandir($dir);
    sort($scanAll);
    $scanDirs = []; $scanFiles = [];
    foreach($scanAll as $fName){
        if ($fName === '.' || $fName === '..') { continue; }
        $fPath = str_replace(DIRECTORY_SEPARATOR, '/', realpath($dir . '/' . $fName));
        if (strlen($excludeRegex) > 0 && preg_match($excludeRegex, $fPath . (is_dir($fPath) ? '/' : ''))) { continue; }
        if (is_dir($fPath)) {
            $scanDirs[] = $fPath;
        } elseif ($onlyFiles >= 0) {
            $scanFiles[] = $fPath;
        }
    }

    foreach ($scanDirs as $pDir) {
        if ($onlyFiles <= 0) {
            $results[] = $pDir;
        }
        if ($maxDepth !== 0) {
            foreach (getDirContents($pDir, $onlyFiles, $excludeRegex, $maxDepth - 1) as $p) {
                $results[] = $p;
            }
        }
    }
    foreach ($scanFiles as $p) {
        $results[] = $p;
    }

    return $results;
}

And if you need relative paths:

function updateKeysWithRelPath(array $paths, string $baseDir, bool $allowBaseDirPath = false): array {
    $results = [];
    $regex = '~^' . preg_quote(str_replace(DIRECTORY_SEPARATOR, '/', realpath($baseDir)), '~') . '(?:/|$)~s';
    $regex = preg_replace('~/~', '/(?:(?!\.\.?/)(?:(?!/).)+/\.\.(?:/|$))?(?:\.(?:/|$))*', $regex); // limited to only one "/xx/../" expr
    if (DIRECTORY_SEPARATOR === '\\') {
        $regex = preg_replace('~/~', '[/\\\\\\\\]', $regex) . 'i';
    }
    foreach ($paths as $p) {
        $rel = preg_replace($regex, '', $p, 1);
        if ($rel === $p) {
            throw new \Exception('Path relativize failed, path "' . $p . '" is not within basedir "' . $baseDir . '".');
        } elseif ($rel === '') {
            if (!$allowBaseDirPath) {
                throw new \Exception('Path relativize failed, basedir path "' . $p . '" not allowed.');
            } else {
                $results[$rel] = './';
            }
        } else {
            $results[$rel] = $p;
        }
    }
    return $results;
}

function getDirContentsWithRelKeys(string $dir, int $onlyFiles = 0, string $excludeRegex = '~/\.git/~', int $maxDepth = -1): array {
    return updateKeysWithRelPath(getDirContents($dir, $onlyFiles, $excludeRegex, $maxDepth), $dir);
}

This version solves/improves:

1. warnings from realpath when PHP open_basedir does not cover the .. directory.
2. does not use reference for the result array
3. allows to exclude directories and files
4. allows to list files/directories only
5. allows to limit the search depth
6. it always sort output with directories first (so directories can be removed/emptied in reverse order)
7. allows to get paths with relative keys
8. heavy optimized for hundred of thousands or even milions of files
9. write for more in the comments :)

Examples:

// list only `*.php` files and skip .git/ and the current file
$onlyPhpFilesExcludeRegex = '~/\.git/|(?<!/|\.php)$|^' . preg_quote(str_replace(DIRECTORY_SEPARATOR, '/', realpath(__FILE__)), '~') . '$~is';

$phpFiles = getDirContents(__DIR__, 1, $onlyPhpFilesExcludeRegex);
print_r($phpFiles);

// with relative keys
$phpFiles = getDirContentsWithRelKeys(__DIR__, 1, $onlyPhpFilesExcludeRegex);
print_r($phpFiles);

// with "include only" regex to include only .html and .txt files with "/*_mails/en/*.(html|txt)" path
'~/\.git/|^(?!.*/(|' . '[^/]+_mails/en/[^/]+\.(?:html|txt)' . ')$)~is'

This is a little modification of majicks answer.
I just changed the array structure returned by the function.

From:

array() => {
    [0] => "test/test.txt"
}

To:

array() => {
    'test/test.txt' => "test.txt"
}

/**
 * @param string $dir
 * @param bool   $recursive
 * @param string $basedir
 *
 * @return array
 */
function getFileListAsArray(string $dir, bool $recursive = true, string $basedir = ''): array {
    if ($dir == '') {
        return array();
    } else {
        $results = array();
        $subresults = array();
    }
    if (!is_dir($dir)) {
        $dir = dirname($dir);
    } // so a files path can be sent
    if ($basedir == '') {
        $basedir = realpath($dir) . DIRECTORY_SEPARATOR;
    }

    $files = scandir($dir);
    foreach ($files as $key => $value) {
        if (($value != '.') && ($value != '..')) {
            $path = realpath($dir . DIRECTORY_SEPARATOR . $value);
            if (is_dir($path)) { // do not combine with the next line or..
                if ($recursive) { // ..non-recursive list will include subdirs
                    $subdirresults = self::getFileListAsArray($path, $recursive, $basedir);
                    $results = array_merge($results, $subdirresults);
                }
            } else { // strip basedir and add to subarray to separate file list
                $subresults[str_replace($basedir, '', $path)] = $value;
            }
        }
    }
    // merge the subarray to give the list of files then subdirectory files
    if (count($subresults) > 0) {
        $results = array_merge($subresults, $results);
    }
    return $results;
}

Might help for those having the exact same expected results like me.

This will print the full path of all files in the given directory, you can also pass other callback functions to recursiveDir.

function printFunc($path){
    echo $path."<br>";
}

function recursiveDir($path, $fileFunc, $dirFunc){
    $openDir = opendir($path);
    while (($file = readdir($openDir)) !== false) {
        $fullFilePath = realpath("$path/$file");
        if ($file[0] != ".") {
            if (is_file($fullFilePath)){
                if (is_callable($fileFunc)){
                    $fileFunc($fullFilePath);
                }
            } else {
                if (is_callable($dirFunc)){
                    $dirFunc($fullFilePath);
                }
                recursiveDir($fullFilePath, $fileFunc, $dirFunc);
            }
        }
    }
}

recursiveDir($dirToScan, 'printFunc', 'printFunc');

Get all the files with filter (2nd argument) and folders in a directory, don't call function when you have . or ...

Your code :

<?php
function getDirContents($dir, $filter = '', &$results = array()) {
    $files = scandir($dir);

    foreach($files as $key => $value){
        $path = realpath($dir.DIRECTORY_SEPARATOR.$value); 

        if(!is_dir($path)) {
            if(empty($filter) || preg_match($filter, $path)) $results[] = $path;
        } elseif($value != "." && $value != "..") {
            getDirContents($path, $filter, $results);
        }
    }

    return $results;
} 

// Simple Call: List all files
var_dump(getDirContents('/xampp/htdocs/WORK'));

// Regex Call: List php files only
var_dump(getDirContents('/xampp/htdocs/WORK', '/\.php$/'));

Output (example) :

// Simple Call
array(13) {
  [0]=> string(69) "/xampp/htdocs/WORK.htaccess"
  [1]=> string(73) "/xampp/htdocs/WORKConverter.php"
  [2]=> string(69) "/xampp/htdocs/WORKEvent.php"
  [3]=> string(70) "/xampp/htdocs/WORKdefault_filter.json"
  [4]=> string(68) "/xampp/htdocs/WORKdefault_filter.xml"
  [5]=> string(80) "/xampp/htdocs/WORKCaching/ApcCache.php"
  [6]=> string(84) "/xampp/htdocs/WORKCaching/CacheFactory.php"
}

// Regex Call
array(13) {
  [0]=> string(69) "/xampp/htdocs/WORKEvent.php"
  [1]=> string(73) "/xampp/htdocs/WORKConverter.php"
  [2]=> string(80) "/xampp/htdocs/WORKCaching/ApcCache.php"
  [3]=> string(84) "/xampp/htdocs/WORKCaching/CacheFactory.php"
}

James Cameron's proposition.

Here's a modified version of Hors answer, works slightly better for my case, as it strips out the base directory that is passed as it goes, and has a recursive switch that can be set to false which is also handy. Plus to make the output more readable, I've separated the file and subdirectory files, so the files are added first then the subdirectory files (see result for what I mean.)

I tried a few other methods and suggestions around and this is what I ended up with. I had another working method already that was very similar, but seemed to fail where there was a subdirectory with no files but that subdirectory had a subsubdirectory with files, it didn't scan the subsubdirectory for files - so some answers may need to be tested for that case.)... anyways thought I'd post my version here too in case someone is looking...

function get_filelist_as_array($dir, $recursive = true, $basedir = '', $include_dirs = false) {
    if ($dir == '') {return array();} else {$results = array(); $subresults = array();}
    if (!is_dir($dir)) {$dir = dirname($dir);} // so a files path can be sent
    if ($basedir == '') {$basedir = realpath($dir).DIRECTORY_SEPARATOR;}

    $files = scandir($dir);
    foreach ($files as $key => $value){
        if ( ($value != '.') && ($value != '..') ) {
            $path = realpath($dir.DIRECTORY_SEPARATOR.$value);
            if (is_dir($path)) {
                // optionally include directories in file list
                if ($include_dirs) {$subresults[] = str_replace($basedir, '', $path);}
                // optionally get file list for all subdirectories
                if ($recursive) {
                    $subdirresults = get_filelist_as_array($path, $recursive, $basedir, $include_dirs);
                    $results = array_merge($results, $subdirresults);
                }
            } else {
                // strip basedir and add to subarray to separate file list
                $subresults[] = str_replace($basedir, '', $path);
            }
        }
    }
    // merge the subarray to give the list of files then subdirectory files
    if (count($subresults) > 0) {$results = array_merge($subresults, $results);}
    return $results;
}

I suppose one thing to be careful of it not to pass a $basedir value to this function when calling it... mostly just pass the $dir (or passing a filepath will work now too) and optionally $recursive as false if and as needed. The result:

[0] => demo-image.png
[1] => filelist.php
[2] => tile.png
[3] => 2015\header.png
[4] => 2015\08\background.jpg

Enjoy! Okay, back to the program I'm actually using this in...

UPDATE Added extra argument for including directories in the file list or not (remembering other arguments will need to be passed to use this.) eg.

$results = get_filelist_as_array($dir, true, '', true);

Here is what I came up with and this is with not much lines of code

function show_files($start) {
    $contents = scandir($start);
    array_splice($contents, 0,2);
    echo "<ul>";
    foreach ( $contents as $item ) {
        if ( is_dir("$start/$item") && (substr($item, 0,1) != '.') ) {
            echo "<li>$item</li>";
            show_files("$start/$item");
        } else {
            echo "<li>$item</li>";
        }
    }
    echo "</ul>";
}

show_files('./');

It outputs something like

..idea
.add.php
.add_task.php
.helpers
 .countries.php
.mysqli_connect.php
.sort.php
.test.js
.test.php
.view_tasks.php

** The dots are the dots of unoordered list.

Hope this helps.

here I have example for that

List all the files and folders in a Directory csv(file) read with PHP recursive function

<?php

/** List all the files and folders in a Directory csv(file) read with PHP recursive function */
function getDirContents($dir, &$results = array()){
    $files = scandir($dir);

    foreach($files as $key => $value){
        $path = realpath($dir.DIRECTORY_SEPARATOR.$value);
        if(!is_dir($path)) {
            $results[] = $path;
        } else if($value != "." && $value != "..") {
            getDirContents($path, $results);
            //$results[] = $path;
        }
    }

    return $results;
}





$files = getDirContents('/xampp/htdocs/medifree/lab');//here folder name where your folders and it's csvfile;


foreach($files as $file){
$csv_file =$file;
$foldername =  explode(DIRECTORY_SEPARATOR,$file);
//using this get your folder name (explode your path);
print_r($foldername);

if (($handle = fopen($csv_file, "r")) !== FALSE) {

fgetcsv($handle); 
while (($data = fgetcsv($handle, 1000, ",")) !== FALSE) {
$num = count($data);
for ($c=0; $c < $num; $c++) {
$col[$c] = $data[$c];
}
}
fclose($handle);
}

}

?>

http://myphpinformation.blogspot.in/2016/05/list-all-files-and-folders-in-directory-csv-file-read-with-php-recursive.html

Add relative path option:

function getDirContents($dir, $relativePath = false)
{
    $fileList = array();
    $iterator = new RecursiveIteratorIterator(new RecursiveDirectoryIterator($dir));
    foreach ($iterator as $file) {
        if ($file->isDir()) continue;
        $path = $file->getPathname();
        if ($relativePath) {
            $path = str_replace($dir, '', $path);
            $path = ltrim($path, '/\\');
        }
        $fileList[] = $path;
    }
    return $fileList;
}

print_r(getDirContents('/path/to/dir'));

print_r(getDirContents('/path/to/dir', true));

Output:

Array
(
    [0] => /path/to/dir/test1.html
    [1] => /path/to/dir/test.html
    [2] => /path/to/dir/index.php
)

Array
(
    [0] => test1.html
    [1] => test.html
    [2] => index.php
)

My proposal without ugly "foreach" control structures is

$iterator = new RecursiveIteratorIterator(new RecursiveDirectoryIterator($path));
$allFiles = array_filter(iterator_to_array($iterator), function($file) {
    return $file->isFile();
});

You may only want to extract the filepath, which you can do so by:

array_keys($allFiles);

Still 4 lines of code, but more straight forward than using a loop or something.

This could help if you wish to get directory contents as an array, ignoring hidden files and directories.

function dir_tree($dir_path)
{
    $rdi = new \RecursiveDirectoryIterator($dir_path);

    $rii = new \RecursiveIteratorIterator($rdi);

    $tree = [];

    foreach ($rii as $splFileInfo) {
        $file_name = $splFileInfo->getFilename();

        // Skip hidden files and directories.
        if ($file_name[0] === '.') {
            continue;
        }

        $path = $splFileInfo->isDir() ? array($file_name => array()) : array($file_name);

        for ($depth = $rii->getDepth() - 1; $depth >= 0; $depth--) {
            $path = array($rii->getSubIterator($depth)->current()->getFilename() => $path);
        }

        $tree = array_merge_recursive($tree, $path);
    }

    return $tree;
}

The result would be something like;

dir_tree(__DIR__.'/public');

[
    'css' => [
        'style.css',
        'style.min.css',
    ],
    'js' => [
        'script.js',
        'script.min.js',
    ],
    'favicon.ico',
]

Source

Here is mine :

function recScan( $mainDir, $allData = array() ) 
{ 
// hide files 
$hidefiles = array( 
".", 
"..", 
".htaccess", 
".htpasswd", 
"index.php", 
"php.ini", 
"error_log" ) ; 

//start reading directory 
$dirContent = scandir( $mainDir ) ; 

foreach ( $dirContent as $key => $content ) 
{ 
$path = $mainDir . '/' . $content ; 

// if is readable / file 
if ( ! in_array( $content, $hidefiles ) ) 
{ 
if ( is_file( $path ) && is_readable( $path ) ) 
{ 
$allData[] = $path ; 
} 

// if is readable / directory 
// Beware ! recursive scan eats ressources ! 
else 
if ( is_dir( $path ) && is_readable( $path ) ) 
{ 
/*recursive*/ 
$allData = recScan( $path, $allData ) ; 
} 
} 
} 

return $allData ; 
}  

$rii = new RecursiveIteratorIterator(new RecursiveDirectoryIterator('path/to/folder'));

$files = array(); 

foreach ($rii as $file) {

    if ($file->isDir()){ 
        continue;
    }

    $files[] = $file->getPathname(); 

}



var_dump($files);

This will bring you all the files with paths.

To whom needs list files first than folders (with alphabetical older).

Can use following function. This is not self calling function. So you will have directory list, directory view, files list and folders list as seperated array also.

I spend two days for this and do not want someone will wast his time for this also, hope helps someone.

function dirlist($dir){
    if(!file_exists($dir)){ return $dir.' does not exists'; }
    $list = array('path' => $dir, 'dirview' => array(), 'dirlist' => array(), 'files' => array(), 'folders' => array());

    $dirs = array($dir);
    while(null !== ($dir = array_pop($dirs))){
        if($dh = opendir($dir)){
            while(false !== ($file = readdir($dh))){
                if($file == '.' || $file == '..') continue;
                $path = $dir.DIRECTORY_SEPARATOR.$file;
                $list['dirlist_natural'][] = $path;
                if(is_dir($path)){
                    $list['dirview'][$dir]['folders'][] = $path;
                    // Bos klasorler while icerisine tekrar girmeyecektir. Klasorun oldugundan emin olalim.
                    if(!isset($list['dirview'][$path])){ $list['dirview'][$path] = array(); }
                    $dirs[] = $path;
                    //if($path == 'D:\Xampp\htdocs\exclusiveyachtcharter.localhost\wp-content\upgrade'){ press($path); press($list['dirview']); die; }
                }
                else{
                    $list['dirview'][$dir]['files'][] = $path;
                }
            }
            closedir($dh);
        }
    }

    // if(!empty($dirlist['dirlist_natural']))  sort($dirlist['dirlist_natural'], SORT_LOCALE_STRING); // delete safe ama gerek kalmadi.

    if(!empty($list['dirview'])) ksort($list['dirview']);

    // Dosyalari dogru siralama yaptiriyoruz. Deniz P. - info[at]netinial.com
    foreach($list['dirview'] as $path => $file){
        if(isset($file['files'])){
            $list['dirlist'][] = $path;
            $list['files'] = array_merge($list['files'], $file['files']);
            $list['dirlist'] = array_merge($list['dirlist'], $file['files']);
        }
        // Add empty folders to the list
        if(is_dir($path) && array_search($path, $list['dirlist']) === false){
            $list['dirlist'][] = $path;
        }
        if(isset($file['folders'])){
            $list['folders'] = array_merge($list['folders'], $file['folders']);
        }
    }

    //press(array_diff($list['dirlist_natural'], $list['dirlist'])); press($list['dirview']); die;

    return $list;
}

will output something like this.

[D:\Xampp\htdocs\exclusiveyachtcharter.localhost] => Array
                (
                    [files] => Array
                        (
                            [0] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\.htaccess
                            [1] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\index.php
                            [2] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\license.txt
                            [3] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\php.php
                            [4] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\readme.html
                            [5] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\wp-activate.php
                            [6] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\wp-blog-header.php
                            [7] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\wp-comments-post.php
                            [8] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\wp-config-sample.php
                            [9] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\wp-config.php
                            [10] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\wp-cron.php
                            [11] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\wp-links-opml.php
                            [12] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\wp-load.php
                            [13] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\wp-login.php
                            [14] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\wp-mail.php
                            [15] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\wp-settings.php
                            [16] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\wp-signup.php
                            [17] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\wp-trackback.php
                            [18] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\xmlrpc.php
                        )

                    [folders] => Array
                        (
                            [0] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\exclusiv_excluwlsql
                            [1] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\wp-admin
                            [2] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\wp-content
                            [3] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\wp-includes
                        )

                )

dirview output

    [dirview] => Array
        (
            [0] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\.htaccess
            [1] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\index.php
            [2] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\license.txt
            [3] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\php.php
            [4] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\readme.html
            [5] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\wp-activate.php
            [6] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\wp-blog-header.php
            [7] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\wp-comments-post.php
            [8] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\wp-config-sample.php
            [9] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\wp-config.php
            [10] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\wp-cron.php
            [11] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\wp-links-opml.php
            [12] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\wp-load.php
            [13] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\wp-login.php
            [14] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\wp-mail.php
            [15] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\wp-settings.php
            [16] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\wp-signup.php
            [17] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\wp-trackback.php
            [18] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\xmlrpc.php
            [19] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost
            [20] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\exclusiv_excluwlsql\exclusiv_excluwl.sql
            [21] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\exclusiv_excluwlsql\exclusiv_excluwl.sql.zip
            [22] => D:\Xampp\htdocs\exclusiveyachtcharter.localhost\exclusiv_excluwlsql
)

@A-312's solution may cause memory problems as it may create a huge array if /xampp/htdocs/WORK contains a lot of files and folders.

If you have PHP 7 then you can use Generators and optimize PHP's memory like this:

function getDirContents($dir) {
    $files = scandir($dir);
    foreach($files as $key => $value){

        $path = realpath($dir.DIRECTORY_SEPARATOR.$value);
        if(!is_dir($path)) {
            yield $path;

        } else if($value != "." && $value != "..") {
           yield from getDirContents($path);
           yield $path;
        }
    }
}

foreach(getDirContents('/xampp/htdocs/WORK') as $value) {
    echo $value."\n";
}

yield from

It's shorter version :

function getDirContents($path) {
    $rii = new RecursiveIteratorIterator(new RecursiveDirectoryIterator($path));

    $files = array(); 
    foreach ($rii as $file)
        if (!$file->isDir())
            $files[] = $file->getPathname();

    return $files;
}

var_dump(getDirContents($path));

This solution did the job for me. The RecursiveIteratorIterator lists all directories and files recursively but unsorted. The program filters the list and sorts it.

I'm sure there is a way to write this shorter; feel free to improve it. It is just a code snippet. You may want to pimp it to your purposes.

<?php

$path = '/pth/to/your/directories/and/files';
// an unsorted array of dirs & files
$files_dirs = iterator_to_array( new RecursiveIteratorIterator(new RecursiveDirectoryIterator($path),RecursiveIteratorIterator::SELF_FIRST) );

echo '<html><body><pre>';
// create a new associative multi-dimensional array with dirs as keys and their files
$dirs_files = array();
foreach($files_dirs as $dir){
 if(is_dir($dir) AND preg_match('/\/\.$/',$dir)){
  $d = preg_replace('/\/\.$/','',$dir);
  $dirs_files[$d] = array();
  foreach($files_dirs as $file){
   if(is_file($file) AND $d == dirname($file)){
    $f = basename($file);
    $dirs_files[$d][] = $f;
   }
  }
 }
}
//print_r($dirs_files);

// sort dirs
ksort($dirs_files);

foreach($dirs_files as $dir => $files){
 $c = substr_count($dir,'/');
 echo  str_pad(' ',$c,' ', STR_PAD_LEFT)."$dir\n";
 // sort files
 asort($files);
 foreach($files as $file){
  echo str_pad(' ',$c,' ', STR_PAD_LEFT)."|_$file\n";
 }
}
echo '</pre></body></html>';

?>

I improved with one check iteration the good code of Hors Sujet to avoid including folders in the result array:

function getDirContents($dir, &$results = array()){

    $files = scandir($dir);

    foreach($files as $key => $value){
        $path = realpath($dir.DIRECTORY_SEPARATOR.$value);
        if(is_dir($path) == false) {
            $results[] = $path;
        }
        else if($value != "." && $value != "..") {
            getDirContents($path, $results);
            if(is_dir($path) == false) {
                $results[] = $path;
            }   
        }
    }
    return $results;

}