PHP里面实现JS的escape和unescape函数

function escape($str) {
  preg_match_all("/[\x80-\xff].|[\x01-\x7f]+/",$str,$r);
  $ar = $r[0];
  foreach($ar as $k=>$v) {
    if(ord($v[0]) < 128)
      $ar[$k] = rawurlencode($v);
    else
      $ar[$k] = "%u".bin2hex(iconv("GB2312","UCS-2",$v));
  }
  return join("",$ar);
}

function unescape($str) {
  $str = rawurldecode($str);
  preg_match_all("/(?:%u.{4})|.+/",$str,$r);
  $ar = $r[0];
  foreach($ar as $k=>$v) {
    if(substr($v,0,2) == "%u" && strlen($v) == 6)
      $ar[$k] = iconv("UCS-2","GB2312",pack("H4",substr($v,-4)));
  }
  return join("",$ar);
}

楼上的是没测试的
楼下的是测试的

function js_unescape($str)
{
        $ret = '';
        $len = strlen($str);

        for ($i = 0; $i < $len; $i++)
        {
                if ($str[$i] == '%' && $str[$i+1] == 'u')
                {
                        $val = hexdec(substr($str, $i+2, 4));

                        if ($val < 0x7f) $ret .= chr($val);
                        else if($val < 0x800) $ret .= chr(0xc0|($val>>6)).chr(0x80|($val&0x3f));
                        else $ret .= chr(0xe0|($val>>12)).chr(0x80|(($val>>6)&0x3f)).chr(0x80|($val&0x3f));

                        $i += 5;
                }
                else if ($str[$i] == '%')
                {
                        $ret .= urldecode(substr($str, $i, 3));
                        $i += 2;
                }
                else $ret .= $str[$i];
        }
        return $ret;
}