Comparing strings:

<?php
$coll = new Collator("fr_CA");
if ($coll->compare("côte", "coté") < 0) {
    echo "less\n";
} else {
    echo "greater\n";
}
?>
Output
less

Ignore case and accents:

<?php
$coll = new Collator("fr_CA");
$coll->setStrength(Collator::PRIMARY);
if ($coll->compare("côte", "cOTé") == 0) {
    echo "same\n";
} else {
    echo "different\n";
}
?>
Output
same