RE: [PHP] running str_replace, it misbehaves!

> -----Original Message----- > From: Allen McCabe [mailto:allenmccabe@gmail.com] > Sent: 16 August 2009 22:07 [...] > Here is an example of my code: > > [code] > > <?php > //ENCRYPT FUNCTIONS > function format_string($string,$functions) > { $funcs = explode(",",$functions); > foreach ($funcs as $func) > { > if (function_exists($func)) $string = $func($string); > } > return $string; > } > function enc_string($string) > { $search = > > array("a","b","c","d","e","f","g","h","i",".........."); > //62 > values > $replace = > array("j9","k8","q7","v6","..........."); //62 > values > $string = str_replace($search, $replace, $string); > $search2 = > > array("9k","8q","7v","6w","5x","4y","3z","2j","................"); > // 126 > values > $string = str_replace($search2, $replace2, $string); > return $string; > } When you feed array search and replace values to str_replace, it runs them in sequence, not in parallel As you haven't given us a full input alphabet above (and, incidentally, you've left out the value of $replace2!), I can't give an example using your encoding, so let's just take, for example: $string = 'word'; and feed it through str_replace(array('d','o','r','w'), array('w9', 'r8', 'o7', 'd6'), $string); This proceeds as follows: d -> w9 = worw9 o -> r8 = wr8rw9 r -> o7 = wo78o7w9 // Note how TWO r->o7 replaces were made here! w -> d6 = d6o78o7d69 // and similarly w->d6 twice! I think this gives you a clue as to what is happening -- the same effect will occur on your second str_replace, as well, giving you your apparent "multiple encode" problem. If you must do this kind of translation, then you need a function that doesn't have this re-replace effect, such as strtr() http://php.net/strtr. But, I have to wonder, why aren't you just using one of the encoding functions readily available in PHP, such as md5() or sha1(), or hash()? Cheers! Mike -- Mike Ford, Electronic Information Developer, Libraries and Learning Innovation, Leeds Metropolitan University, C507, Civic Quarter Campus, Woodhouse Lane, LEEDS,  LS1 3HE,  United Kingdom Email: m.ford@leedsmet.ac.uk Tel: +44 113 812 4730 To view the terms under which this email is distributed, please go to http://disclaimer.leedsmet.ac.uk/email.htm