用拉丁语对应替换外来字符，用连字符替换空格（PHP）

I have this code:

$header = 'weird character->>>ÅÅÖÄ';
$header = strtolower(str_replace(array('  ', ' '), '-', preg_replace('/[^a-zA-Z0-9 s]/', '', trim($header))));

It should output weird-characteraaoa, but it doesn't. It just removes the ÅÅÖÄ-letters. Any idea why this isn't working? I'm using UTF-8 if that has something to do with it

This is a hard problem since not all languages can match-up well with ASCII characters.

However, @AlixAxel has the current best implementation I've ever seen in his phunction framework.

    public static function Slug($string, $slug = '-', $extra = null)
    {
        return strtolower(trim(preg_replace('~[^0-9a-z' . preg_quote($extra, '~') . ']+~i', $slug, self::Unaccent($string)), $slug));
    }

    public static function Unaccent($string)
    {
        if (extension_loaded('intl') === true)
        {
            $string = Normalizer::normalize($string, Normalizer::FORM_KD);
        }

        if (strpos($string = htmlentities($string, ENT_QUOTES, 'UTF-8'), '&') !== false)
        {
            $string = html_entity_decode(preg_replace('~&([a-z]{1,2})(?:acute|caron|cedil|circ|grave|lig|orn|ring|slash|tilde|uml);~i', '$1', $string), ENT_QUOTES, 'UTF-8');
        }

        return $string;
    }

I think you may want to create a custom function as below and use it:

function normalize ($string) {
   $table = array('Å'=>'A', 'Ä'=>'A','Ö'=>'O');
   return strtr($string, $table);
}

Please add the chars you want to use.