PHP使用适合阅读的格式显示文件大小的方法

// A much better and accurate version can be found

// in Aidan's PHP Repository: 

// http://aidanlister.com/repos/v/function.size_readable.php 
/**

 * Returns a human readable filesize

 *

 * @author      wesman20 (php.net)

 * @author      Jonas John

 * @version     0.3

 * @link        http://www.jonasjohn.de/snippets/php/readable-filesize.htm 
 */

function HumanReadableFilesize($size) {

    // Adapted from: http://www.php.net/manual/en/function.filesize.php 
    $mod = 1024;

    $units = explode(' ','B KB MB GB TB PB');

    for ($i = 0; $size > $mod; $i++) {

        $size /= $mod;

    }

    return round($size, 2) . ' ' . $units[$i];

}