Help in converting a Javascript function to PHP.

Hi all,

i have the following function taht I tried to convert to PHP, but I faild because I'm not fully aware of Javascript Syntax, it basically converts a string of HEX numbers into a normail string.

function hexToString (h) {
  var r = "";
  for (var i= (h.substr(0, 2)=="0x")?2:0; i<h.length; i+=2) {r += String.fromCharCode (parseInt (h.substr (i, 2), 16));}
  return r;
this is basically a reverse of

function stringToHex (s) {
  var r = "0x";
  var hexes = new Array ("0","1","2","3","4","5","6","7","8","9","a","b","c","d","e","f");
  for (var i=0; i<s.length; i++) {r += hexes [s.charCodeAt(i) >> 4] + hexes [s.charCodeAt(i) & 0xf];}
  return r;

Which is in PHP:

function stringToHex ($s) {
  $r = "0x";
  $hexes = array ("0","1","2","3","4","5","6","7","8","9","a","b","c","d","e","f");
  for ($i=0; $i<strlen($s); $i++) {$r .= ($hexes [(ord($s{$i}) >> 4)] . $hexes [(ord($s{$i}) & 0xf)]);}
  return $r;

Any help would be great.
Who is Participating?
hernst42Connect With a Mentor Commented:
the String to hex is implemented in PHP with the function


In the comments you also find the function to convert hex2bin:

function hex2bin($hexdata){
for( $i = 0; $i < strlen( $hexdata ); $i += 2 )
eval( '$bindata .= "\x' . substr( $hexdata, $i, 2 ) . '";' );
return $bindata;}
kalmenAuthor Commented:

I used these two functions from the link you provided:
function stringToHex ($s) {
   $len = strlen($s);
   for ($i=0; $i<$len; $i++) $data.=sprintf("%02x",ord(substr($s,$i,1)));
   return $data;

function hexToString ($h) {
   $len = strlen($h);
   for ($i=0;$i<$len;$i+=2) $data.=chr(hexdec(substr($h,$i,2)));
   return $data;
My problem is here,

My Javascript functions do not work the same way, I'm trying to implement the exact reverse of string2Hex in JS  as HextoString in PHP.

Now, my Javascript function string2Hex encodes "wazzap?" as 0x77617a7a61703f
and my PHP hextostring function encodes "wazzap? as 77617a7a61703f ..

Ooops.. I just noticed the 0x... My bad.. I'll just add it and see how it goes.

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