php实现Javascript的escape和unescape函数

function escape($str) {
preg_match_all("/[/xc2-/xdf][/x80-/xbf]+|[/xe0-/xef][/x80-/xbf]{2}|[/xf0-/xff][/x80-/xbf]{3}|[/x01-/x7f]+/e",$str,$r);	//匹配utf-8字符
$str = $r[0];
$l = count($str);
for($i=0; $i <$l; $i++) {
$value = ord($str[$i][0]);
if($value < 223) {
$str[$i] = rawurlencode($str[$i]);
} else {
$str[$i] = "%u".strtoupper(bin2hex(mb_convert_encoding($str[$i],"UCS-2","UTF-8")));
}
}
return join("",$str);
}

function unescape($str)
{
$str = rawurldecode($str);
preg_match_all("/%u.{4}|&#x.{4};|&#d+;|.+/U",$str,$r);
$ar = $r[0];
foreach($ar as $k=>$v)
{
if(substr($v,0,2) == "%u")
{
//$ar[$k] = iconv("UCS-2","UTF-8",pack("H4",substr($v,-4)));
$ar[$k] = mb_convert_encoding(pack("H4",substr($v,-4)),"UTF-8","UCS-2");
}
elseif(substr($v,0,3) == "&#x")
{
//$ar[$k] = iconv("UCS-2","UTF-8",pack("H4",substr($v,3,-1)));
$ar[$k] = mb_convert_encoding(pack("H4",substr($v,3,-1)),"UTF-8","UCS-2");
}
elseif(substr($v,0,2) == "&#")
{
//$ar[$k] = iconv("UCS-2","UTF-8",pack("n",substr($v,2,-1)));
$ar[$k] = mb_convert_encoding(pack("n",substr($v,2,-1)),"UTF-8","UCS-2");
}
}
return join("",$ar);
}