Sometimes we need the string to only contain unaccented characters, for example urls, xml, filename etc.
Expecially before PHP6, You may think of function setlocale() and iconv(), but they are evil…
If you’re writing code for yourself, to be used on a server you control, locales could be made to work if your server has locales installed which support UTF-8. That would mean functions like strtolower behave correctly.
But this is no use if you’re writing applications which will be installed by third parties (like these for example) because it’s system specific (it’s not even just OS specific). If the default system locale does not support UTF-8, in theory your application could change the locale “on the fly” using setlocale but in practice that requires two things; that there is a locale available on the system which supports UTF-8 (not guaranteed) and that the correct locale identifier string can be found (there a definately differences between Windows and *Nix locale identifiers and even amongst the Unixes believe there are variations e.g. FreeBSD). What’s more, you can’t rely on users to be able to change the locale correctly to suit your applications needs – on a shared host they probably won’t be able to change the locale for the user that Apache is running with. Bottom line – locales are not the way to go for applications intended to be “write once, run anywhere”.
— http://www.phpwact.org/php/i18n/utf-8
Here is just the function to replace accented characters by normal english letters.
It contain a long list of characters matching table and use strstr() to replace accents.
[codesyntax lang=”php” lines=”no”]
function replaceAccents($str)
{
$normalizeChars = array(
"\xC3\x80" => "A", "\xC3\x81" => "A", "\xC3\x82" => "A", "\xC3\x83" => "A", "\xC3\x84" => "A",
"\xC3\x85" => "A", "\xC3\x86" => "AE", "\xC3\x87" => "C", "\xC3\x88" => "E", "\xC3\x89" => "E",
"\xC3\x8A" => "E", "\xC3\x8B" => "E", "\xC3\x8C" => "I", "\xC3\x8D" => "I", "\xC3\x8E" => "I",
"\xC3\x8F" => "I", "\xC3\x90" => "D", "\xC3\x91" => "N", "\xC3\x92" => "O", "\xC3\x93" => "O",
"\xC3\x94" => "O", "\xC3\x95" => "O", "\xC3\x96" => "O", "\xC3\x98" => "O", "\xC3\x99" => "U",
"\xC3\x9A" => "U", "\xC3\x9B" => "U", "\xC3\x9C" => "U", "\xC3\x9D" => "Y", "\xC3\x9E" => "P",
"\xC3\x9F" => "ss", "\xC3\xA0" => "a", "\xC3\xA1" => "a", "\xC3\xA2" => "a", "\xC3\xA3" => "a",
"\xC3\xA4" => "a", "\xC3\xA5" => "a", "\xC3\xA6" => "ae", "\xC3\xA7" => "c", "\xC3\xA8" => "e",
"\xC3\xA9" => "e", "\xC3\xAA" => "e", "\xC3\xAB" => "e", "\xC3\xAC" => "i", "\xC3\xAD" => "i",
"\xC3\xAE" => "i", "\xC3\xAF" => "i", "\xC3\xB0" => "o", "\xC3\xB1" => "n", "\xC3\xB2" => "o",
"\xC3\xB3" => "o", "\xC3\xB4" => "o", "\xC3\xB5" => "o", "\xC3\xB6" => "o", "\xC3\xB8" => "o",
"\xC3\xB9" => "u", "\xC3\xBA" => "u", "\xC3\xBB" => "u", "\xC3\xBC" => "u", "\xC3\xBD" => "y",
"\xC3\xBE" => "p", "\xC3\xBF" => "y", "\xC4\x80" => "A", "\xC4\x81" => "a", "\xC4\x82" => "A",
"\xC4\x83" => "a", "\xC4\x84" => "A", "\xC4\x85" => "a", "\xC4\x86" => "C", "\xC4\x87" => "c",
"\xC4\x88" => "C", "\xC4\x89" => "c", "\xC4\x8A" => "C", "\xC4\x8B" => "c", "\xC4\x8C" => "C",
"\xC4\x8D" => "c", "\xC4\x8E" => "D", "\xC4\x8F" => "d", "\xC4\x90" => "D", "\xC4\x91" => "d",
"\xC4\x92" => "E", "\xC4\x93" => "e", "\xC4\x94" => "E", "\xC4\x95" => "e", "\xC4\x96" => "E",
"\xC4\x97" => "e", "\xC4\x98" => "E", "\xC4\x99" => "e", "\xC4\x9A" => "E", "\xC4\x9B" => "e",
"\xC4\x9C" => "G", "\xC4\x9D" => "g", "\xC4\x9E" => "G", "\xC4\x9F" => "g", "\xC4\xA0" => "G",
"\xC4\xA1" => "g", "\xC4\xA2" => "G", "\xC4\xA3" => "g", "\xC4\xA4" => "H", "\xC4\xA5" => "h",
"\xC4\xA6" => "H", "\xC4\xA7" => "h", "\xC4\xA8" => "I", "\xC4\xA9" => "i", "\xC4\xAA" => "I",
"\xC4\xAB" => "i", "\xC4\xAC" => "I", "\xC4\xAD" => "i", "\xC4\xAE" => "I", "\xC4\xAF" => "i",
"\xC4\xB0" => "I", "\xC4\xB1" => "i", "\xC4\xB2" => "IJ", "\xC4\xB3" => "ij", "\xC4\xB4" => "J",
"\xC4\xB5" => "j", "\xC4\xB6" => "K", "\xC4\xB7" => "k", "\xC4\xB8" => "k", "\xC4\xB9" => "L",
"\xC4\xBA" => "l", "\xC4\xBB" => "L", "\xC4\xBC" => "l", "\xC4\xBD" => "L", "\xC4\xBE" => "l",
"\xC4\xBF" => "L", "\xC5\x80" => "l", "\xC5\x81" => "L", "\xC5\x82" => "l", "\xC5\x83" => "N",
"\xC5\x84" => "n", "\xC5\x85" => "N", "\xC5\x86" => "n", "\xC5\x87" => "N", "\xC5\x88" => "n",
"\xC5\x89" => "n", "\xC5\x8A" => "N", "\xC5\x8B" => "n", "\xC5\x8C" => "O", "\xC5\x8D" => "o",
"\xC5\x8E" => "O", "\xC5\x8F" => "o", "\xC5\x90" => "O", "\xC5\x91" => "o", "\xC5\x92" => "CE",
"\xC5\x93" => "ce", "\xC5\x94" => "R", "\xC5\x95" => "r", "\xC5\x96" => "R", "\xC5\x97" => "r",
"\xC5\x98" => "R", "\xC5\x99" => "r", "\xC5\x9A" => "S", "\xC5\x9B" => "s", "\xC5\x9C" => "S",
"\xC5\x9D" => "s", "\xC5\x9E" => "S", "\xC5\x9F" => "s", "\xC5\xA0" => "S", "\xC5\xA1" => "s",
"\xC5\xA2" => "T", "\xC5\xA3" => "t", "\xC5\xA4" => "T", "\xC5\xA5" => "t", "\xC5\xA6" => "T",
"\xC5\xA7" => "t", "\xC5\xA8" => "U", "\xC5\xA9" => "u", "\xC5\xAA" => "U", "\xC5\xAB" => "u",
"\xC5\xAC" => "U", "\xC5\xAD" => "u", "\xC5\xAE" => "U", "\xC5\xAF" => "u", "\xC5\xB0" => "U",
"\xC5\xB1" => "u", "\xC5\xB2" => "U", "\xC5\xB3" => "u", "\xC5\xB4" => "W", "\xC5\xB5" => "w",
"\xC5\xB6" => "Y", "\xC5\xB7" => "y", "\xC5\xB8" => "Y", "\xC5\xB9" => "Z", "\xC5\xBA" => "z",
"\xC5\xBB" => "Z", "\xC5\xBC" => "z", "\xC5\xBD" => "Z", "\xC5\xBE" => "z", "\xC6\x8F" => "E",
"\xC6\xA0" => "O", "\xC6\xA1" => "o", "\xC6\xAF" => "U", "\xC6\xB0" => "u", "\xC7\x8D" => "A",
"\xC7\x8E" => "a", "\xC7\x8F" => "I", "\xC7\x90" => "i", "\xC7\x91" => "O", "\xC7\x92" => "o",
"\xC7\x93" => "U", "\xC7\x94" => "u", "\xC7\x95" => "U", "\xC7\x96" => "u", "\xC7\x97" => "U",
"\xC7\x98" => "u", "\xC7\x99" => "U", "\xC7\x9A" => "u", "\xC7\x9B" => "U", "\xC7\x9C" => "u",
"\xC7\xBA" => "A", "\xC7\xBB" => "a", "\xC7\xBC" => "AE", "\xC7\xBD" => "ae", "\xC7\xBE" => "O",
"\xC7\xBF" => "o", "\xC9\x99" => "e",
);
$str = strtr($str, $normalizeChars);
$str = trim(preg_replace('/[^\w\d_ -]/si', '', $str)); //remove all illegal chars
$str = preg_replace('/\s+/', ' ', $str);
return $str;
}
[/codesyntax]