the great escape How to implement the escape decoding function under PHP

GB2312 encoding:

Copy code The code is as follows:

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

Copy Code The code is as follows:

function 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;
}

The above introduces the implementation method of the great escape escape decoding function under PHP, including the content of the great escape. I hope it will be helpful to friends who are interested in PHP tutorials.