Brainstorming functions to convert diacritics into ASCII

remove_diacritics.php

/*
    Convert common diacritics in portuguese language.
*/
function convertPortugueseDiacritics($string)
{
    $from = 'áéíóúãõàèìòùçñüïÁÉÍÓÚÃÕÀÈÌÒÙÇÑÜÏ';
    $to =   'aeiouaoaeioucnuiAEIOUAOAEIOUCNUI';

    $from = preg_split('//u', $from, -1, PREG_SPLIT_NO_EMPTY);
    $to = str_split($to);

    $map = array_combine($from, $to);
    return strtr($string, $map);
}

/*
    Convert diacritics from all UTF-8 (as possible)
    but leaves only letters, numbers and spaces, to
    prevent conversion garbage.
*/
function convertDiacritics($string)
{
    $string = iconv('UTF-8', 'US-ASCII//TRANSLIT', $string);
    $string = preg_replace('|[^a-zA-Z0-9 ]|', '', $string);
    return $string;
}