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Convert Accented Characters

For instance, if you want to use a string as part of a URL but need to make it safe for that kind of use.

function replace_accents($str) {
   $str = htmlentities($str, ENT_COMPAT, "UTF-8");
   $str = preg_replace('/&([a-zA-Z])(uml|acute|grave|circ|tilde);/','$1',$str);
   return html_entity_decode($str);


  1. Or you just use the functions that are already implemented in PHP ><

    $unsafe = 'Hello Daniël';
    $safe = urlencode($unsafe);
    $transfered = urldecode($_GET['data']);
    • the $unsafe value pulled through urlencode gives you this: “Hello%20Dani%C3%ABl”
      That are all valid characters inside a URL. It even works on so called multi byte characters, which are used in Korean, Japanese, Mandarin and similar languages. I found that out the hard way when some survey system started chopping up comments.

      The JavaScript equivalent is encodeURI / encodeURIComponent and to reverse that you use decodeURI / decodeURIComponent.

      var response, safe, unsafe = 'Hello Daniël';
      safe = encodeURIComponent(unsafe);
      response = decodeURIComponent(ajaxResponse);
  2. The go the other way around, when facing encoded characters, you might want to get the character that relates the most to an accented variant. E.g.: You want to store a song with DJ Tiësto in the title, but want it to turn out like DJ Tiesto when creating a filename in your script.

    function transform($title){
    	// Support ASCII list characters in encoded format
    		$pointer = strpos($title,'&#');
    		$plength = 5;
    		$first = substr($title,0,$pointer);
    		$last = substr($title,$pointer+$plength);
    		$pnr = substr($title,$pointer+2,3);
    		$backstring = '';
    		$last = $backstring.$last;
    		$title = $first.htmlentities(chr($pnr)).$last;
    	$title = str_replace(
    	$title = str_replace(
    	while(strpos($title,'  ')!==false){
    		$title=str_replace('  ',' ',$title);
    	return $title;
  3. the original snippet doesn’t cut it. Unicodes that aren’t covered by htmlentities() are ignored altogether. If you (safely) want to transform an UTF-8 string to alph-anumeric for the use in URLs, give urlify() a shot.

  4. Julien
    Permalink to comment#

    I have done this :

    function replace_accents($str) {
    $str = htmlentities($str);
    $str = preg_replace(‘/&([a-zA-Z])(uml|acute|grave|circ|tilde|cedil|elig|ring|th|slash|zlig|horn);/’,’$1′,$str);
    return html_entity_decode($str);

  5. Julien
    Permalink to comment#

    function replace_accents($str) {
    $str = htmlentities($str);
    $str = preg_replace('/&([a-zA-Z])(uml|acute|grave|circ|tilde|cedil|elig|ring|th|slash|zlig|horn);/','$1',$str);
    return html_entity_decode($str);

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