note 99925 modified in function.utf8-encode by danbrown

Avoiding use of preg_match to detect if utf8_encode is needed: <?php $string = $string_input; // avoid being destructive $string = preg_replace("#[\x09\x0A\x0D\x20-\x7E]#" ,"",$string); // ASCII $string = preg_replace("#[\xC2-\xDF][\x80-\xBF]#" ,"",$string); // non-overlong 2-byte $string = preg_replace("#\xE0[\xA0-\xBF][\x80-\xBF]#" ,"",$string); // excluding overlongs $string = preg_replace("#[\xE1-\xEC\xEE\xEF][\x80-\xBF]{2}#","",$string); // straight 3-byte $string = preg_replace("#\xED[\x80-\x9F][\x80-\xBF]#" ,"",$string); // excluding surrogates $string = preg_replace("#\xF0[\x90-\xBF][\x80-\xBF]{2}#","",$string); // planes 1-3 $string = preg_replace("#[\xF1-\xF3][\x80-\xBF]{3}#" ,"",$string); // planes 4-15 $string = preg_replace("#\xF4[\x80-\x8F][\x80-\xBF]{2}#","",$string); // plane 16 $rc = ($string == ""?true:false); ?> --was-- Avoiding use of preg_match to detect if utf8_encode is needed: $string = $string_input; // avoid being destructive $string = preg_replace("#[\x09\x0A\x0D\x20-\x7E]#" ,"",$string); // ASCII $string = preg_replace("#[\xC2-\xDF][\x80-\xBF]#" ,"",$string); // non-overlong 2-byte $string = preg_replace("#\xE0[\xA0-\xBF][\x80-\xBF]#" ,"",$string); // excluding overlongs $string = preg_replace("#[\xE1-\xEC\xEE\xEF][\x80-\xBF]{2}#","",$string); // straight 3-byte $string = preg_replace("#\xED[\x80-\x9F][\x80-\xBF]#" ,"",$string); // excluding surrogates $string = preg_replace("#\xF0[\x90-\xBF][\x80-\xBF]{2}#","",$string); // planes 1-3 $string = preg_replace("#[\xF1-\xF3][\x80-\xBF]{3}#" ,"",$string); // planes 4-15 $string = preg_replace("#\xF4[\x80-\x8F][\x80-\xBF]{2}#","",$string); // plane 16 $rc = ($string == ""?true:false); http://php.net/manual/en/function.utf8-encode.php