Compare two string and ignore (but not replace) accents. PHP

Question

I got (for example) two strings:

$a = "joao";
$b = "joão";

if ( strtoupper($a) == strtoupper($b)) {
    echo $b;
}

I want it to be true even tho the accentuation. However I need it to ignore the accentuation instead of replacing because I need it to echo "joão" and not "joao".

All answers I've seen replace "ã" for "a" instead of making the comparison true. I've been reading about normalizing it, but I can't make it work either. Any ideas? Thank you.

Answer 1

I would like to share an elegant solution that avoids the usage of htmlentities and that doesn't need to manually list all chars replacements. It is the traduction in php of the answers to this post.

function removeAccents($str) {
    return preg_replace('/[\x{0300}-\x{036f}]/u',"",normalizer_normalize($str,Normalizer::FORM_D));
}

$a = "joaoaaeeA";
$b = "joãoâàéèÀ";

var_dump(removeAccents($a) === removeAccents($b));

Output:

bool(true)

Answer 2

Just convert the accents to their non-accented counter part and then compare strings. The function in my answer will remove the accents for you.

function removeAccents($string) {
    return strtolower(trim(preg_replace('~[^0-9a-z]+~i', '-', preg_replace('~&([a-z]{1,2})(acute|cedil|circ|grave|lig|orn|ring|slash|th|tilde|uml);~i', '$1', htmlentities($string, ENT_QUOTES, 'UTF-8'))), ' '));
}

$a = "joaoaaeeA";
$b = "joãoâàéèÀ";

var_dump(removeAccents($a) === removeAccents($b));

Output:

bool(true)

Demo