public static function upload_image($filename, $where)
 {
     if ($tmp_name = $_FILES["{$filename}"]['tmp_name']) {
         $type = substr($_FILES["{$filename}"]['type'], strripos($_FILES["{$filename}"]['type'], '/') + 1);
         $name = date('Ymd') . Framework::password_gen(20, 0) . '.' . $type;
         $dir = $_SERVER['DOCUMENT_ROOT'] . '/img/' . $where . '/';
         //$dir = ' '.$where.'/';
         if (!move_uploaded_file($tmp_name, $dir . $name)) {
             return false;
         }
     } else {
         return false;
     }
     return $name;
 }