php中的DirectoryIterator跟RecursiveDirectoryIterator

php中的DirectoryIterator和RecursiveDirectoryIterator
php中,可以用用DirectoryIterator获取指定目录的文件或者目录.

RecursiveDirectoryIterator 获取目录下所有的文件,包括子目录 ,其中搭配:
RecursiveIteratorIterator使用.
(RecursiveIteratorIterator是个递归迭代器，其后可选带四个参数（只能任一）

RecursiveIteratorIterator::LEAVES_ONLY
默认，已在__construct中设定使用
作用是去枝留叶，跳过空节点，只递归取实值
举例就是
1.递归文件夹取文件时跳过文件夹本身，只取文件夹下面的文件，输出的项全部是file（文件和各级子文件夹的文件）
2.多维数组就跳过前几维的key，而取value，输出的每一项都不是array
3.XML只取值(text)，不输出节点名，当然还要视乎你设定获取xml什么内容

RecursiveIteratorIterator::SELF_FIRST
各项都包含，例如递归文件夹就会连同子文件夹名称也作为其中项输出，顺序是先父后子

RecursiveIteratorIterator::CHILD_FIRST
同上，但顺序是先子后父，./test/test.php会在./test（文件夹）前面)

$path = "/tmp/"; 
$objects = new RecursiveIteratorIterator(new RecursiveDirectoryIterator($path)); 
foreach($objects as $object) 
{ 
  $tmpFile['link'] = $object->getPath(); 
  $tmpFile['name'] = $object->getFileName(); 
  $tmpFile['type'] = $object->isFile() ? 'file' : 'dir'; 
  $tmpFile['size'] = _cal_size($object->getSize()); 
  $tmpFile['mtime'] = $object->getMTime(); 
  $arrFile[] = $tmpFile; 
} 
print_r($arrFile); 
/*
output:
Array
(
    [0] => Array
        (
            [link] => /tmp
            [name] => scim-panel-socket-:0-root
            [type] => dir
            [size] => 0b
            [mtime] => 1222049895
        )

    [1] => Array
        (
            [link] => /tmp/.font-unix
            [name] => fs7100
            [type] => dir
            [size] => 0b
            [mtime] => 1241417372
        )
)
*/ 

再来看个例子:

/*** the target directory, no trailling slash ***/
$directory = './';

try
    {
        /*** check if we have a valid directory ***/
        if( !is_dir($directory) )
        {
            throw new Exception('Directory does not exist!'."\n");
        }

        /*** check if we have permission to rename the files ***/
        if( !is_writable( $directory ))
        {
            throw new Exception('You do not have renaming permissions!'."\n");
        }

   
        /**
        *
        * @collapse white space
        *
        * @param string $string
        *
        * @return string
        *
        */
        function collapseWhiteSpace($string)
        {
            return  preg_replace('/\s+/', ' ', $string);
        }

        /**
        * @convert file names to nice names
        *
        * @param string $filename
        *
        * @return string
        *
        */
        function safe_names($filename)
        {
            $filename = collapseWhiteSpace($filename);
            $filename = str_replace(' ', '-', $filename);
            $filename = preg_replace('/[^a-z0-9-.]/i','',$filename);
            return  strtolower($filename);
        }

        $it = new RecursiveIteratorIterator(new RecursiveDirectoryIterator($directory, 0));
        /*** loop directly over the object ***/
        while($it->valid())
            {
            /*** check if value is a directory ***/
            if(!$it->isDot())
            {
                if(!is_writable($directory.'/'.$it->getSubPathName()))
                {
                    echo 'Permission Denied: '.$directory.'/'.$it->getSubPathName()."\n";
                }
                else
                {
                    /*** the old file name ***/
                    $old_file = $directory.'/'.$it->getSubPathName();

                    /*** the new file name ***/
                    $new_file = $directory.'/'.$it->getSubPath().'/'.safe_names($it->current());
                   
                    /*** rename the file ***/
                    rename ($old_file, $new_file);

                    /*** a little message to say file is converted ***/
                    echo 'Renamed '. $directory.'/'.$it->getSubPathName() ."\n";
                }
            }
            /*** move to the next iteration ***/
            $it->next();
        }
       
        /*** when we are all done let the user know ***/
        echo 'Renaming of files complete'."\n";
    }
    catch(Exception $e)
    {
        echo $e->getMessage()."\n";
    }
?>