Sanitizes the HTML select element's options.
The function is recursive to support optgroups.
function prepare_filter_select_options(&$options) {
foreach ($options as $value => $label) {
// Recurse for optgroups.
if (is_array($label)) {
$this
->prepare_filter_select_options($options[$value]);
}
elseif (is_object($label)) {
$this
->prepare_filter_select_options($options[$value]->option);
}
else {
$options[$value] = strip_tags(decode_entities($label));
}
}
}