drupal: standard way for creating a slug from a string
You can use built in Drupal functions to do this.
$string = drupal_clean_css_identifier($string);
$slug = drupal_html_class($string);
functions will do the trick for you.
I ended up using the slug function explained here (at the end of the article, you have to click in order to see the source code).
This does what I need and a couple things more, without needing to include external modules and the like.
Pasting the code below for easy future reference:
/**
* Calculate a slug with a maximum length for a string.
*
* @param $string
* The string you want to calculate a slug for.
* @param $length
* The maximum length the slug can have.
* @return
* A string representing the slug
*/
function slug($string, $length = -1, $separator = '-') {
// transliterate
$string = transliterate($string);
// lowercase
$string = strtolower($string);
// replace non alphanumeric and non underscore charachters by separator
$string = preg_replace('/[^a-z0-9]/i', $separator, $string);
// replace multiple occurences of separator by one instance
$string = preg_replace('/'. preg_quote($separator) .'['. preg_quote($separator) .']*/', $separator, $string);
// cut off to maximum length
if ($length > -1 && strlen($string) > $length) {
$string = substr($string, 0, $length);
}
// remove separator from start and end of string
$string = preg_replace('/'. preg_quote($separator) .'$/', '', $string);
$string = preg_replace('/^'. preg_quote($separator) .'/', '', $string);
return $string;
}
/**
* Transliterate a given string.
*
* @param $string
* The string you want to transliterate.
* @return
* A string representing the transliterated version of the input string.
*/
function transliterate($string) {
static $charmap;
if (!$charmap) {
$charmap = array(
// Decompositions for Latin-1 Supplement
chr(195) . chr(128) => 'A', chr(195) . chr(129) => 'A',
chr(195) . chr(130) => 'A', chr(195) . chr(131) => 'A',
chr(195) . chr(132) => 'A', chr(195) . chr(133) => 'A',
chr(195) . chr(135) => 'C', chr(195) . chr(136) => 'E',
chr(195) . chr(137) => 'E', chr(195) . chr(138) => 'E',
chr(195) . chr(139) => 'E', chr(195) . chr(140) => 'I',
chr(195) . chr(141) => 'I', chr(195) . chr(142) => 'I',
chr(195) . chr(143) => 'I', chr(195) . chr(145) => 'N',
chr(195) . chr(146) => 'O', chr(195) . chr(147) => 'O',
chr(195) . chr(148) => 'O', chr(195) . chr(149) => 'O',
chr(195) . chr(150) => 'O', chr(195) . chr(153) => 'U',
chr(195) . chr(154) => 'U', chr(195) . chr(155) => 'U',
chr(195) . chr(156) => 'U', chr(195) . chr(157) => 'Y',
chr(195) . chr(159) => 's', chr(195) . chr(160) => 'a',
chr(195) . chr(161) => 'a', chr(195) . chr(162) => 'a',
chr(195) . chr(163) => 'a', chr(195) . chr(164) => 'a',
chr(195) . chr(165) => 'a', chr(195) . chr(167) => 'c',
chr(195) . chr(168) => 'e', chr(195) . chr(169) => 'e',
chr(195) . chr(170) => 'e', chr(195) . chr(171) => 'e',
chr(195) . chr(172) => 'i', chr(195) . chr(173) => 'i',
chr(195) . chr(174) => 'i', chr(195) . chr(175) => 'i',
chr(195) . chr(177) => 'n', chr(195) . chr(178) => 'o',
chr(195) . chr(179) => 'o', chr(195) . chr(180) => 'o',
chr(195) . chr(181) => 'o', chr(195) . chr(182) => 'o',
chr(195) . chr(182) => 'o', chr(195) . chr(185) => 'u',
chr(195) . chr(186) => 'u', chr(195) . chr(187) => 'u',
chr(195) . chr(188) => 'u', chr(195) . chr(189) => 'y',
chr(195) . chr(191) => 'y',
// Decompositions for Latin Extended-A
chr(196) . chr(128) => 'A', chr(196) . chr(129) => 'a',
chr(196) . chr(130) => 'A', chr(196) . chr(131) => 'a',
chr(196) . chr(132) => 'A', chr(196) . chr(133) => 'a',
chr(196) . chr(134) => 'C', chr(196) . chr(135) => 'c',
chr(196) . chr(136) => 'C', chr(196) . chr(137) => 'c',
chr(196) . chr(138) => 'C', chr(196) . chr(139) => 'c',
chr(196) . chr(140) => 'C', chr(196) . chr(141) => 'c',
chr(196) . chr(142) => 'D', chr(196) . chr(143) => 'd',
chr(196) . chr(144) => 'D', chr(196) . chr(145) => 'd',
chr(196) . chr(146) => 'E', chr(196) . chr(147) => 'e',
chr(196) . chr(148) => 'E', chr(196) . chr(149) => 'e',
chr(196) . chr(150) => 'E', chr(196) . chr(151) => 'e',
chr(196) . chr(152) => 'E', chr(196) . chr(153) => 'e',
chr(196) . chr(154) => 'E', chr(196) . chr(155) => 'e',
chr(196) . chr(156) => 'G', chr(196) . chr(157) => 'g',
chr(196) . chr(158) => 'G', chr(196) . chr(159) => 'g',
chr(196) . chr(160) => 'G', chr(196) . chr(161) => 'g',
chr(196) . chr(162) => 'G', chr(196) . chr(163) => 'g',
chr(196) . chr(164) => 'H', chr(196) . chr(165) => 'h',
chr(196) . chr(166) => 'H', chr(196) . chr(167) => 'h',
chr(196) . chr(168) => 'I', chr(196) . chr(169) => 'i',
chr(196) . chr(170) => 'I', chr(196) . chr(171) => 'i',
chr(196) . chr(172) => 'I', chr(196) . chr(173) => 'i',
chr(196) . chr(174) => 'I', chr(196) . chr(175) => 'i',
chr(196) . chr(176) => 'I', chr(196) . chr(177) => 'i',
chr(196) . chr(178) => 'IJ', chr(196) . chr(179) => 'ij',
chr(196) . chr(180) => 'J', chr(196) . chr(181) => 'j',
chr(196) . chr(182) => 'K', chr(196) . chr(183) => 'k',
chr(196) . chr(184) => 'k', chr(196) . chr(185) => 'L',
chr(196) . chr(186) => 'l', chr(196) . chr(187) => 'L',
chr(196) . chr(188) => 'l', chr(196) . chr(189) => 'L',
chr(196) . chr(190) => 'l', chr(196) . chr(191) => 'L',
chr(197) . chr(128) => 'l', chr(197) . chr(129) => 'L',
chr(197) . chr(130) => 'l', chr(197) . chr(131) => 'N',
chr(197) . chr(132) => 'n', chr(197) . chr(133) => 'N',
chr(197) . chr(134) => 'n', chr(197) . chr(135) => 'N',
chr(197) . chr(136) => 'n', chr(197) . chr(137) => 'N',
chr(197) . chr(138) => 'n', chr(197) . chr(139) => 'N',
chr(197) . chr(140) => 'O', chr(197) . chr(141) => 'o',
chr(197) . chr(142) => 'O', chr(197) . chr(143) => 'o',
chr(197) . chr(144) => 'O', chr(197) . chr(145) => 'o',
chr(197) . chr(146) => 'OE', chr(197) . chr(147) => 'oe',
chr(197) . chr(148) => 'R', chr(197) . chr(149) => 'r',
chr(197) . chr(150) => 'R', chr(197) . chr(151) => 'r',
chr(197) . chr(152) => 'R', chr(197) . chr(153) => 'r',
chr(197) . chr(154) => 'S', chr(197) . chr(155) => 's',
chr(197) . chr(156) => 'S', chr(197) . chr(157) => 's',
chr(197) . chr(158) => 'S', chr(197) . chr(159) => 's',
chr(197) . chr(160) => 'S', chr(197) . chr(161) => 's',
chr(197) . chr(162) => 'T', chr(197) . chr(163) => 't',
chr(197) . chr(164) => 'T', chr(197) . chr(165) => 't',
chr(197) . chr(166) => 'T', chr(197) . chr(167) => 't',
chr(197) . chr(168) => 'U', chr(197) . chr(169) => 'u',
chr(197) . chr(170) => 'U', chr(197) . chr(171) => 'u',
chr(197) . chr(172) => 'U', chr(197) . chr(173) => 'u',
chr(197) . chr(174) => 'U', chr(197) . chr(175) => 'u',
chr(197) . chr(176) => 'U', chr(197) . chr(177) => 'u',
chr(197) . chr(178) => 'U', chr(197) . chr(179) => 'u',
chr(197) . chr(180) => 'W', chr(197) . chr(181) => 'w',
chr(197) . chr(182) => 'Y', chr(197) . chr(183) => 'y',
chr(197) . chr(184) => 'Y', chr(197) . chr(185) => 'Z',
chr(197) . chr(186) => 'z', chr(197) . chr(187) => 'Z',
chr(197) . chr(188) => 'z', chr(197) . chr(189) => 'Z',
chr(197) . chr(190) => 'z', chr(197) . chr(191) => 's',
// Euro Sign
chr(226) . chr(130) . chr(172) => 'E'
);
}
// transliterate
return strtr($string, $charmap);
}
function is_slug($str) {
return $str == slug($str);
}
There's also this from d7 which you can copy to your project:
http://api.drupal.org/api/function/drupal_clean_css_identifier/7
i am a happy Zen theme user, thus i've met this wonderful function that comes with it: zen_id_safe http://api.lullabot.com/zen_id_safe
it does not depend on any other theme function, so you can just copy it to your module or theme and use it. it is a pretty small and simple function, so i will just paste it here for convenience.
function zen_id_safe($string) {
// Replace with dashes anything that isn't A-Z, numbers, dashes, or underscores.
return strtolower(preg_replace('/[^a-zA-Z0-9-]+/', '-', $string));
}