PHP版的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); 
}