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  • readdir()

    (PHP 4, PHP 5, PHP 7)

    从目录句柄中读取条目

    说明

    readdir([resource $dir_handle]): string

    返回目录中下一个文件的文件名。文件名以在文件系统中的排序返回。

    参数

    $dir_handle

    目录句柄的resource,之前由opendir()打开

    返回值

    成功则返回文件名或者在失败时返回FALSE

    Warning

    此函数可能返回布尔值FALSE,但也可能返回等同于FALSE的非布尔值。请阅读布尔类型章节以获取更多信息。应使用===运算符来测试此函数的返回值。

    范例

    列出目录中的所有文件

    请留意下面例子中检查readdir()返回值的风格。这里明确地测试返回值是否全等于(值和类型都相同——更多信息参见比较运算符)FALSE,否则任何目录项的名称求值为FALSE的都会导致循环停止(例如一个目录名为“0”)。

    <?php
    // 注意在 4.0.0-RC2 之前不存在 !== 运算符
    if ($handle = opendir('/path/to/files')) {
        echo "Directory handle: $handle\n";
        echo "Files:\n";
        /* 这是正确地遍历目录方法 */
        while (false !== ($file = readdir($handle))) {
            echo "$file\n";
        }
        /* 这是错误地遍历目录的方法 */
        while ($file = readdir($handle)) {
            echo "$file\n";
        }
        closedir($handle);
    }
    ?>
    

    列出当前目录的所有文件并去掉...

    <?php
    if ($handle = opendir('.')) {
        while (false !== ($file = readdir($handle))) {
            if ($file != "." && $file != "..") {
                echo "$file\n";
            }
        }
        closedir($handle);
    }
    ?>
    

    参见

    • is_dir() 判断给定文件名是否是一个目录
    • glob() 寻找与模式匹配的文件路径
    • opendir() 打开目录句柄
    • scandir() 列出指定路径中的文件和目录
    A function I created to non-recursively get the path of all files and folders including sub-directories of a given folder.
    Though I have not tested it completely, it seems to be working.
    <?php
    /**
     * Finds path, relative to the given root folder, of all files and directories in the given directory and its sub-directories non recursively.
     * Will return an array of the form 
     * array(
     *  'files' => [],
     *  'dirs' => [],
     * )
     * @author sreekumar
     * @param string $root
     * @result array
     */
    function read_all_files($root = '.'){
     $files = array('files'=>array(), 'dirs'=>array());
     $directories = array();
     $last_letter = $root[strlen($root)-1];
     $root = ($last_letter == '\\' || $last_letter == '/') ? $root : $root.DIRECTORY_SEPARATOR;
     
     $directories[] = $root;
     
     while (sizeof($directories)) {
      $dir = array_pop($directories);
      if ($handle = opendir($dir)) {
       while (false !== ($file = readdir($handle))) {
        if ($file == '.' || $file == '..') {
         continue;
        }
        $file = $dir.$file;
        if (is_dir($file)) {
         $directory_path = $file.DIRECTORY_SEPARATOR;
         array_push($directories, $directory_path);
         $files['dirs'][] = $directory_path;
        } elseif (is_file($file)) {
         $files['files'][] = $file;
        }
       }
       closedir($handle);
      }
     }
     
     return $files;
    }
    ?>
    
    Looking through the examples, I can't see any that do a simple check on the value of the directory resource that opendir returns and is subsequently used by readdir.
    If opendir returns false, and you simply pass this to the readdir call in the while loop, you will get an infinite loop. 
    A simple test helps prevent this:
    <?php
    $dir = opendir($path);
    while ($dir && ($file = readdir($dir)) !== false) {
     // do stuff
    }
    ?>
    
    Here is an updated version of preg_find() [which has been linked from the glob() man page for years] - this function should provide most of what you want back from reading files, directories, different sorting methods, recursion, and perhaps most powerful of all the ability to pattern match with a PCRE regex.
    You can get preg_find here: http://www.pgregg.com/projects/php/preg_find/preg_find.php.txt
    or if you prefer colourful .phps format: http://www.pgregg.com/projects/php/preg_find/preg_find.phps
    or scoll down to the end of this note.
    I wrote several examples on how to use it on my blog at: http://www.pgregg.com/forums/viewtopic.php?tid=73
    simple glob() type replacement:
    $files = preg_find('/./', $dir);
    recursive?
    $files = preg_find('/./', $dir, PREG_FIND_RECURSIVE);
    pattern match? find all .php files:
    $files = preg_find('/\.php$/D', $dir, PREG_FIND_RECURSIVE);
    sorted alphabetically?
    $files = preg_find('/\.php$/D', $dir, PREG_FIND_RECURSIVE|PREG_FIND_SORTKEYS);
    sorted in by filesize, in descending order?
    $files = preg_find('/./', $dir,
     PREG_FIND_RECURSIVE|PREG_FIND_RETURNASSOC |PREG_FIND_SORTFILESIZE|PREG_FIND_SORTDESC);
    $files=array_keys($files);
    sorted by date modified?
    $files = preg_find('/./', $dir,
     PREG_FIND_RECURSIVE|PREG_FIND_RETURNASSOC |PREG_FIND_SORTMODIFIED);
    $files=array_keys($files);
    Ok, the PHP note says my note is too long, so please click on one of the above links to get it.
    A variation on listing all the files in a directory recursively. The code illustrates a basic technique : the use of an auxiliary function. It avoids building temporary lists which are merged on the way back. Note that the array which collects the information must be passed by reference.
    <?php
    function listdir($dir='.') {
      if (!is_dir($dir)) {
        return false;
      }
      
      $files = array();
      listdiraux($dir, $files);
      return $files;
    }
    function listdiraux($dir, &$files) {
      $handle = opendir($dir);
      while (($file = readdir($handle)) !== false) {
        if ($file == '.' || $file == '..') {
          continue;
        }
        $filepath = $dir == '.' ? $file : $dir . '/' . $file;
        if (is_link($filepath))
          continue;
        if (is_file($filepath))
          $files[] = $filepath;
        else if (is_dir($filepath))
          listdiraux($filepath, $files);
      }
      closedir($handle);
    }
    $files = listdir('.');
    sort($files, SORT_LOCALE_STRING);
    foreach ($files as $f) {
      echo $f, "\n";
    }
    ?>
    
    code:
    <?php
        function permission($filename)
        {
          $perms = fileperms($filename);
          if   (($perms & 0xC000) == 0xC000) { $info = 's'; }
          elseif (($perms & 0xA000) == 0xA000) { $info = 'l'; }
          elseif (($perms & 0x8000) == 0x8000) { $info = '-'; }
          elseif (($perms & 0x6000) == 0x6000) { $info = 'b'; }
          elseif (($perms & 0x4000) == 0x4000) { $info = 'd'; }
          elseif (($perms & 0x2000) == 0x2000) { $info = 'c'; }
          elseif (($perms & 0x1000) == 0x1000) { $info = 'p'; }
          else                 { $info = 'u'; }
          // владелец
          $info .= (($perms & 0x0100) ? 'r' : '-');
          $info .= (($perms & 0x0080) ? 'w' : '-');
          $info .= (($perms & 0x0040) ? (($perms & 0x0800) ? 's' : 'x' ) : (($perms & 0x0800) ? 'S' : '-'));
          // группа
          $info .= (($perms & 0x0020) ? 'r' : '-');
          $info .= (($perms & 0x0010) ? 'w' : '-');
          $info .= (($perms & 0x0008) ? (($perms & 0x0400) ? 's' : 'x' ) : (($perms & 0x0400) ? 'S' : '-'));
          // все
          $info .= (($perms & 0x0004) ? 'r' : '-');
          $info .= (($perms & 0x0002) ? 'w' : '-');
          $info .= (($perms & 0x0001) ? (($perms & 0x0200) ? 't' : 'x' ) : (($perms & 0x0200) ? 'T' : '-'));
          return $info;
        }
        function dir_list($dir)
        {
          if ($dir[strlen($dir)-1] != '/') $dir .= '/';
          if (!is_dir($dir)) return array();
          $dir_handle = opendir($dir);
          $dir_objects = array();
          while ($object = readdir($dir_handle))
            if (!in_array($object, array('.','..')))
            {
              $filename  = $dir . $object;
              $file_object = array(
                          'name' => $object,
                          'size' => filesize($filename),
                          'perm' => permission($filename),
                          'type' => filetype($filename),
                          'time' => date("d F Y H:i:s", filemtime($filename))
                        );
              $dir_objects[] = $file_object;
            }
          return $dir_objects;
        }
    ?>
    call:
    <?php
        print_r(dir_list('/path/to/you/dir/'));
    ?>
    output sample:
    Array
    (
      [0] => Array
        (
          [name] => api
          [size] => 0
          [perm] => drwxrwxrwx
          [type] => dir
          [time] => 28 May 2007 01:55:02
        )
      [1] => Array
        (
          [name] => classes
          [size] => 0
          [perm] => drwxrwxrwx
          [type] => dir
          [time] => 26 May 2007 00:56:44
        )
      [2] => Array
        (
          [name] => config.inc.php
          [size] => 143
          [perm] => -rw-rw-rw-
          [type] => file
          [time] => 26 May 2007 13:13:19
        )
      [3] => Array
        (
          [name] => index.php
          [size] => 131
          [perm] => -rw-rw-rw-
          [type] => file
          [time] => 26 May 2007 22:15:18
        )
      [4] => Array
        (
          [name] => modules
          [size] => 0
          [perm] => drwxrwxrwx
          [type] => dir
          [time] => 28 May 2007 00:47:40
        )
      [5] => Array
        (
          [name] => temp
          [size] => 0
          [perm] => drwxrwxrwx
          [type] => dir
          [time] => 28 May 2007 04:49:33
        )
    )
    Thought I would include what I wrote to get a random image from a directory.
    <?php
    $image_dir = 'images';
    $count = 0;
    if ($handle = opendir($image_dir)) {
      $retval = array();
      while (false !== ($file = readdir($handle))) {
        if (($file <> ".") && ($file <> "..")) {
        $retval[$count] = $file;
        $count = $count + 1;
          }
      }
      closedir($handle);
    }
    shuffle($retval);
    $current_image = $retval[0];
    ?>
    [NOTE BY danbrown AT php DOT net: Contains a bugfix/typofix inspired by 'ffd8' on 19-JUN-09.]
    <?php 
     // if( $entry[0] != '.' ) best for ' . ' and ' .. '
          $d = dir( '.' );
          echo "Pointeur : " . $d->handle . "\n";
          echo "Chemin : " . $d->path . "\n";
          while (false !== ($entry = $d->read())) {
            if($entry[0] != '.') {
              echo $entry, PHP_EOL;
            }
          }
          $d->close();
    ?>
    
    Regarding the warning:
    This function may return Boolean FALSE, but may also return a non-Boolean value which evaluates to FALSE.
    Of course, this means that if you use:
    <?php
      if($entry = readdir($handle) == false) …
    ?>
    or
    <?php
      while($entry = readdir($handle)) …
    ?>
    you may get a false false, as it were.
    As far as I can tell, the only time this would actually occur is if you encounter an entry of 0.
    According to
    https://www.php.net/manual/en/language.types.boolean.php#language.types.boolean.casting
    this appears to be the only string which will evaluate to false.
    PHP includes and alternative boolean operators whose precedence is below assignment. This means that an expression of the form
    <?php
      if(($a = something()) && $a !== false) … ;
    ?>
    can be written as 
    <?php
      if($a = something() and $a !== false) … ;
    ?>
    In this case, the loop can be written as:
    <?php
      while ($entry = readdir($handle) and $entry !== false) {
        //  etc
      }
    ?>
    
    If dir_handle is not a proper resource, null will be returned instead of false.
    loop through folders and sub folders with option to remove specific files.
    <?php
    function listFolderFiles($dir,$exclude){
      $ffs = scandir($dir);
      echo '<ul class="ulli">';
      foreach($ffs as $ff){
        if(is_array($exclude) and !in_array($ff,$exclude)){
          if($ff != '.' && $ff != '..'){
          if(!is_dir($dir.'/'.$ff)){
          echo '<li><a href="edit_page.php?path='.ltrim($dir.'/'.$ff,'./').'">'.$ff.'</a>';
          } else {
          echo '<li>'.$ff;  
          }
          if(is_dir($dir.'/'.$ff)) listFolderFiles($dir.'/'.$ff,$exclude);
          echo '</li>';
          }
        }
      }
      echo '</ul>';
    }
    listFolderFiles('.',array('index.php','edit_page.php'));
    ?>
    
    ## List and Rename all files on recursive directories with "recursive directory name" as template + filename
    ## Advice: other files in the same directory will result in a warning 
    ## scriptname : Recursive Dir_Renfiles_dirname-filename.php
    <?php
    if ($handle = opendir('.')) {
      while (false !== ($file = readdir($handle))) {
            if ($file != "." && $file != ".." && $file != "Recursive Dir_Renfiles_dirname-filename.php") {
              echo "$file";
        echo "<br>";
              $count = -1;
               $handle2 = @opendir($file);
                while (false !== ($file2 = @readdir($handle2))) {
                echo "$file2";   
                if ($count <10 ){ @rename("$file/$file2", "$file/$file"."_$file2");}
                else { @rename("$file/$file2", "$file/$file"."_$file2");}
                echo "<br>";
                 $count = $count + 1;
                  }
           echo "<br>";
        }
      }
      closedir($handle);
    }
    ?>
    
    Get all files on recursive directories in single array.
    <?php
    /*
     * mrlemonade ~
     */
    function getFilesFromDir($dir) {
     $files = array();
     if ($handle = opendir($dir)) {
      while (false !== ($file = readdir($handle))) {
        if ($file != "." && $file != "..") {
          if(is_dir($dir.'/'.$file)) {
            $dir2 = $dir.'/'.$file;
            $files[] = getFilesFromDir($dir2);
          }
          else {
           $files[] = $dir.'/'.$file;
          }
        }
      }
      closedir($handle);
     }
     return array_flat($files);
    }
    function array_flat($array) {
     foreach($array as $a) {
      if(is_array($a)) {
       $tmp = array_merge($tmp, array_flat($a));
      }
      else {
       $tmp[] = $a;
      }
     }
     return $tmp;
    }
    // Usage
    $dir = '/data';
    $foo = getFilesFromDir($dir);
    print_r($foo);
    ?>
    
    Please be aware that readdir() and opendir() etc will return sorted directory listings automatically on some operating systems, whilst others it will not.
    On later versions of windows, you can usually be guaranteed alphabetically sorted file listings from readdir(), and on Linux there is no such guarantee. If you require any particular sort order you should read the results to an array and use asort() or rsort() on it, or similar, to get the results into the order you need.
    this simple function will index the directories and sub-directories of a given dir
    <?php
    function get_dirs($dir){
      global $dirs;
      if (!isset($dirs)){$dirs = '';}
      if(substr($dir,-1) !== '\\'){$dir .= '\\';}
      if ($handle = opendir($dir)){
        while (false !== ($file = readdir($handle))){
          if (filetype($dir.$file) === 'dir' && $file != "." && $file != ".."){
            clearstatcache();
            $dirs .= $file . "\n";
            get_dirs($dir . $file);
          }
        }
        closedir($handle);
      }
      return $dirs;
    }
    ?>
    
    A very flexible function to recursively list all files in a directory with the option to perform a custom set of actions on those files and/or include extra information about them in the returned data.
     ----------
     SYNTAX:
      $array = process_dir ( $dir , $recursive = FALSE )
        $dir (STRING)  = Directory to process
     $recursive (BOOLEAN) = [Optional] Recursive if set to TRUE
     RETURN VALUES:
     The function returns an indexed array, one entry for every file. Each entry is an associative array, containing the basic information 'filename' (name of file) and 'dirpath' (directory component of path to file), and any additional keys you configure. Returns FALSE on failure.
     ----------
     To allow you to configure another key, the entry for each file is stored in an array, "$entry" for each iteration. You can easily return any additional data for a given file using $entry['keyname'] = ... (Note that this data can be any variable type - string, bool, float, resource etc)
     There is a string variable "$path" available, which contains the full path of the current file, relative to the initial "$dir" supplied at function call. This data is also available in it's constituent parts, "$dir" and "$file". Actions for each file can be constructed on the basis of these variables. The variables "$list", "$handle" and "$recursive" should not be used within your code.
     ----------
     Simply insert you code into the sections indicated by the comments below and your away!
     The following example returns filename, filepath, and file modified time (in a human-readable string) for all items, filesize for all files but not directories, and a resource stream for all files with 'log' in the filename (but not *.log files).
    <?php
     function process_dir($dir,$recursive = FALSE) {
      if (is_dir($dir)) {
       for ($list = array(),$handle = opendir($dir); (FALSE !== ($file = readdir($handle)));) {
        if (($file != '.' && $file != '..') && (file_exists($path = $dir.'/'.$file))) {
         if (is_dir($path) && ($recursive)) {
          $list = array_merge($list, process_dir($path, TRUE));
         } else {
          $entry = array('filename' => $file, 'dirpath' => $dir);
     //---------------------------------------------------------//
     //           - SECTION 1 -            //
     //     Actions to be performed on ALL ITEMS      //
     //-----------------  Begin Editable  ------------------//
     $entry['modtime'] = filemtime($path);
     //-----------------   End Editable   ------------------//
          do if (!is_dir($path)) {
     //---------------------------------------------------------//
     //           - SECTION 2 -            //
     //     Actions to be performed on FILES ONLY      //
     //-----------------  Begin Editable  ------------------//
     $entry['size'] = filesize($path);
     if (strstr(pathinfo($path,PATHINFO_BASENAME),'log')) {
      if (!$entry['handle'] = fopen($path,r)) $entry['handle'] = "FAIL";
     }
     
     //-----------------   End Editable   ------------------//
           break;
          } else {
     //---------------------------------------------------------//
     //           - SECTION 3 -            //
     //    Actions to be performed on DIRECTORIES ONLY    //
     //-----------------  Begin Editable  ------------------//
     //-----------------   End Editable   ------------------//
           break;
          } while (FALSE);
          $list[] = $entry;
         }
        }
       }
       closedir($handle);
       return $list;
      } else return FALSE;
     }
      
     $result = process_dir('C:/webserver/Apache2/httpdocs/processdir',TRUE);
     // Output each opened file and then close
     foreach ($result as $file) {
      if (is_resource($file['handle'])) {
        echo "\n\nFILE (" . $file['dirpath'].'/'.$file['filename'] . "):\n\n" . fread($file['handle'], filesize($file['dirpath'].'/'.$file['filename']));
        fclose($file['handle']);
      }
     }
    ?>
    
    Below will return an array of file names and folders in directory
    <?php
    function ReadFolderDirectory($dir = "root_dir/here")
      {
        $listDir = array();
        if($handler = opendir($dir)) {
          while (($sub = readdir($handler)) !== FALSE) {
            if ($sub != "." && $sub != ".." && $sub != "Thumb.db") {
              if(is_file($dir."/".$sub)) {
                $listDir[] = $sub;
              }elseif(is_dir($dir."/".$sub)){
                $listDir[$sub] = $this->ReadFolderDirectory($dir."/".$sub); 
              }
            }
          }  
          closedir($handler);
        }
        return $listDir;  
      }
    ?>
    
    This is a nice quick full dir read - sorry for my bad english ;)
    <?php
    function ReadDirs($dir,$em){
      if ($handle = opendir($dir)) {
      while (false !== ($file = readdir($handle))) {
        if ($file != "." && $file != ".." && $file != "Thumb.db") {
          if(is_dir($dir.$file)){
            echo $em."&raquo; ".$file.'<br>';
            ReadDirs($dir.$file."/",$em."&nbsp;&nbsp;");
          }
        }
      }
      closedir($handle);
      }
    }
    ?>
    
    <?php
    // Sample function to recursively return all files within a directory.
    // http://www.pgregg.com/projects/php/code/recursive_readdir.phps
    Function listdir($start_dir='.') {
     $files = array();
     if (is_dir($start_dir)) {
      $fh = opendir($start_dir);
      while (($file = readdir($fh)) !== false) {
       # loop through the files, skipping . and .., and recursing if necessary
       if (strcmp($file, '.')==0 || strcmp($file, '..')==0) continue;
       $filepath = $start_dir . '/' . $file;
       if ( is_dir($filepath) )
        $files = array_merge($files, listdir($filepath));
       else
        array_push($files, $filepath);
      }
      closedir($fh);
     } else {
      # false if the function was called with an invalid non-directory argument
      $files = false;
     }
     return $files;
    }
    $files = listdir('.');
    print_r($files);
    ?>
    
    <?php
    if ($handle = opendir('../')) {
      
      while($entry = readdir($handle)){
        $ent[] = $entry;
      }
      
      echo $ent[0]; // Access To Custom Directory or File;
      closedir($handle);
    }
    ?>
    
    Here's a handy function you can use to list the files in the directory you specify, their type (dir or file) and whether they are hidden. 
    You could modify it to do other things too.
    <?php
    function listDirs($where){
    echo "<table border=\"1\"><tr><td><b>Name</b></td><td><b>Type</b></td>";
    echo "<td><b>Invisible (Hidden)?</b></td></tr>";
      $itemHandler=opendir($where);
      $i=0;
      while(($item=readdir($itemHandler)) !== false){
        if(substr($item, 0, 1)!="."){
          if(is_dir($item)){
            echo "<tr><td>$item</td><td>Directory</td><td>No</td></tr>";
          }else{
            echo "<tr><td>$item</td><td>File</td><td>No</td></tr>";
          }
          $i++;
        }else{
          if(is_dir($item)){
            echo "<tr><td>$item</td><td>Directory</td><td>Yes</td></tr>";
          }else{
            echo "<tr><td>$item</td><td>File</td><td>Yes</td></tr>";
          }
          $i++;
        }
        }
    echo "</table>";
    }
    ?>
    Then call it like this.
    <?php
    listDirs(DIR);
    ?>
    Example:
    <?php
    listDirs("/tests/directorylisting");
    ?>
    You get a table like this.
    Name  Type  Invisible (Hidden)?
    .  Directory  Yes
    ..  Directory  Yes
    .DS_Store  File  Yes
    .localized  File  Yes
    index.php  File  No
    OOOLS  Directory  No
    QwerpWiki.php  File  No
    I'm on 5.4.21 this function returns null after . and .. on an empty directory. ZendServer for IBMi
    Find a file or folder within a directory. Say we want will loop n times by all subdirectories of a root directory and find a particular folder or file and know your address.
    In my case I needed to find each existing file in a directory metadata.opf a Calibre library and take all the data for each document this, if we consider that this directory had 20,000 folders author is a task that is humanly impossible . This recursive algorithm achieves do my homework. I hope it will help you.
    <?php
    $root = '../Classes';
    $search_parameter = "CachedObjectStorageFactory.php";
    //if we call the function spider as spider($root); 
    //will show all the directory content including subdirectories
    //if we call the function spider as spider('../Classes', 'Shared');
    //and will show the address of the directory
    spider($root, $search_parameter);
    closedir();
      
    function spider($dir,$fileName=""){
      
      $handle = opendir($dir);
       
      while($file= readdir($handle)){
        if($file != "." && $file != ".."){
            
         if($fileName=="") 
           echo $dir."/".$file."<br>"; 
        else
          if($file == $fileName)    
          echo $dir."/".$file."<br>";      
          
             
        if(!is_file($dir."/".$file))       
          spider($dir."/".$file,$fileName);
         
       }  
      }
      
    }   
    ?>
    
    Warning when using readdir() on certain versions of CentOS on NFS-mounted directories:
    This is not a bug with PHP's readdir, but a bug with certain versions of CentOS's readdir implementation. According to Post #6213 in the CentOS Bugs forum, when using CentOS kernel versions 2.6.18-348 through 2.6.18-348.3.1, invoking readdir on an NFS-mounted directory may not return all the entries. Since PHP's readdir() uses this library, the issue is manifest in PHP as well.
    According to the post, upgrading to version 2.6.18-348.4.1.el5 should solve the issue, though I haven't tried it.
    glob() does NOT seem to suffer from this same vulnerability.
    Handy little function that returns the number of files (not directories) that exists under a directory. 
    Choose if you want the function to recurse through sub-directories with the second parameter - 
    the default mode (false) is just to count the files directly under the supplied path.
    <?php
     /**
      * Return the number of files that resides under a directory.
      * 
      * @return integer
      * @param  string (required)  The directory you want to start in
      * @param  boolean (optional) Recursive counting. Default to FALSE. 
      * @param  integer (optional) Initial value of file count
      */ 
     function num_files($dir, $recursive=false, $counter=0) {
      static $counter;
      if(is_dir($dir)) {
       if($dh = opendir($dir)) {
        while(($file = readdir($dh)) !== false) {
         if($file != "." && $file != "..") {
           $counter = (is_dir($dir."/".$file)) ? num_files($dir."/".$file, $recursive, $counter) : $counter+1;
         }
        }
        closedir($dh);
       }
      }
      return $counter;
     }
     // Usage:
     $nfiles = num_files("/home/kchr", true); // count all files that resides under /home/kchr, including subdirs
     $nfiles = num_files("/tmp"); // count the files directly under /tmp
    ?>
    
    This function is used to display random image i.e. at header position of a site. It reads the whole directory and then randomly print the image. I think it may be useful for someone.
    <?php
    if ($handle = opendir('images/')) {
      $dir_array = array();
      while (false !== ($file = readdir($handle))) {
        if($file!="." && $file!=".."){
          $dir_array[] = $file;
        }
      }
      echo $dir_array[rand(0,count($dir_array)-1)];
      closedir($handle);
    }
    ?>
    
    this function recurrsively goes to a particular depth and stops after the depth is reached.
    function read_path($root = '.', $depth = 1) {
        if($depth == 0) {
          return;
        }
        $last_letter = $root[strlen($root)-1];
         $root = ($last_letter == '\\' || $last_letter == '/') ? $root : $root.DIRECTORY_SEPARATOR;
         $files = array('files'=>array(), 'dirs'=>array());
         if ($handle = opendir($root)) {
           while (false !== ($file = readdir($handle))) {
            if ($file == '.' || $file == '..') {
               continue;
            }
            $file = $root.$file;
            if (is_dir($file)) {
               $directory_path = $file.DIRECTORY_SEPARATOR;
              $files['dirs'][$directory_path] = NULL;
            } elseif (is_file($file)) {
              $files['files'][] = $file;
            }
           }
           closedir($handle);
        }
         $done = [$root=>$files];
         foreach ($done[$root]['dirs'] as $key=>$value) {
           $done[$root]['dirs'][$key] = $this->read_path($key, $depth-1);
         }
         return $done[$root];
      }
    It should work, but it'll be better to read section 13.1.3 Cache-control Mechanisms of RFC 2616 available at http://rfc.net/rfc2616.html before you start with confusing proxies on the way from you and the client.
    Reading it is the best way to learn how proxies work, what should you do to modify cache-related headers of your documents and what you should never do again. :-)
    And of course not reading RFCs is the best way to never learn how internet works and the best way to behave like Microsoft corp.
    Have a nice day!
    Jirka Pech
    Yet another view files by extension
    /* NOTE:
     * /a-d = do not include directories
     * /b  = show files in bare mode ( no dates or filesize )
     */
    <?php
    $dir = '.\\img\\';  // reminder: escape your slashes
    $filetype = "*.png";
    $filelist = shell_exec( "dir {$dir}{$filetype} /a-d /b" );
    $file_arr = explode( "\n", $filelist );
    array_pop( $file_arr ); // last line is always blank
    print_r( $file_arr );
    ?>
    

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