PHP Transliteration

Question

Are there any solutions that will convert all foreign characters to A-z equivalents? I have searched extensively on Google and could not find a solution or even a list of characters and equivalents. The reason is I want to display A-z only URLs, plus plenty of other trip ups when dealing with these characters.

Answer 1

The problem with your query is that it is a very hard thing to do. Not all glyphs in most languages have a-z equivalents, all glyphs have phonetic equivalents (but these are words not letters), if you are just dealing with Latin based languages then things are a little easier but you still have issues with things like I-mutation.

Your best solution word be to come up with a crude list of phonetic sounds -> a-z equivalents, it won't be perfect but without any more information on you exact requirements it is hard to develop a solution.

Answer 2

The strtr manual page lists a few possibilities in the comments, such as

function normalize ($string) {
    $table = array(
        'Š'=>'S', 'š'=>'s', 'Đ'=>'Dj', 'đ'=>'dj', 'Ž'=>'Z', 'ž'=>'z', 'Č'=>'C', 'č'=>'c', 'Ć'=>'C', 'ć'=>'c',
        'À'=>'A', 'Á'=>'A', 'Â'=>'A', 'Ã'=>'A', 'Ä'=>'A', 'Å'=>'A', 'Æ'=>'A', 'Ç'=>'C', 'È'=>'E', 'É'=>'E',
        'Ê'=>'E', 'Ë'=>'E', 'Ì'=>'I', 'Í'=>'I', 'Î'=>'I', 'Ï'=>'I', 'Ñ'=>'N', 'Ò'=>'O', 'Ó'=>'O', 'Ô'=>'O',
        'Õ'=>'O', 'Ö'=>'O', 'Ø'=>'O', 'Ù'=>'U', 'Ú'=>'U', 'Û'=>'U', 'Ü'=>'U', 'Ý'=>'Y', 'Þ'=>'B', 'ß'=>'Ss',
        'à'=>'a', 'á'=>'a', 'â'=>'a', 'ã'=>'a', 'ä'=>'a', 'å'=>'a', 'æ'=>'a', 'ç'=>'c', 'è'=>'e', 'é'=>'e',
        'ê'=>'e', 'ë'=>'e', 'ì'=>'i', 'í'=>'i', 'î'=>'i', 'ï'=>'i', 'ð'=>'o', 'ñ'=>'n', 'ò'=>'o', 'ó'=>'o',
        'ô'=>'o', 'õ'=>'o', 'ö'=>'o', 'ø'=>'o', 'ù'=>'u', 'ú'=>'u', 'û'=>'u', 'ý'=>'y', 'ý'=>'y', 'þ'=>'b',
        'ÿ'=>'y', 'Ŕ'=>'R', 'ŕ'=>'r',
    );

    return strtr($string, $table);
}

Answer 3

You can use iconv, which has a special transliteration encoding.

When the string "//TRANSLIT" is appended to tocode, transliteration is activated. This means that when a character cannot be represented in the target character set, it can be approximated through one or several characters that look similar to the original character.

-- http://www.gnu.org/software/libiconv/documentation/libiconv/iconv_open.3.html

See here for a complete example that matches your use case.

Answer 4

If you don't have access to iconv and if you don't want to use long lookup tables like the one Sebastian P. suggested you can take advantage of the HTML entity representation for each character like this:

$string = preg_replace('~&([a-z]{1,2})(acute|cedil|circ|grave|lig|orn|ring|slash|th|tilde|uml);~i', '$1', htmlentities($string, ENT_COMPAT, 'UTF-8'));

As far as I'm aware of it doesn't work for Chinese, Japanese and other exotic charsets but works just fine for all the other languages.

Answer 5

If you are using iconv then make sure your locale is set correctly before you try the transliteration, otherwise some characters will not be correctly transliterated

setlocale(LC_CTYPE, 'en_US.UTF8');