WooCommerce Select Dropdown With Optgroup On Checkout

Question

I\'m using WordPress 5.0.2 with WooCommerce 3.5.3 and I have created a select dropdown on the checkout page, it works good, however I want to add

Answer 1

You can use this code it will works for you

add_filter('woocommerce_form_field_select', function ($html, $unused, $args, $value) {
if (empty($args['options'])) {
    return $html;
}
$option_groups = ['-' => []];
$options = '';
foreach ($args['options'] as $option_key => $option_text) {
    $option = array_map('trim', explode(':', $option_text));
    if (count($option) >= 2) {
        $option_groups[array_shift($option)][$option_key] = implode(':', $option);
    } else {
        $option_groups['-'][$option_key] = $option[0];
    }
}
foreach ($option_groups as $group => $option) {
    if ($group !== '-') $options .= '';
    foreach ($option as $option_key => $option_text) {
        if ($option_key === '') {
            // If we have a blank option, select2 needs a placeholder
            if (empty($args['placeholder'])) {
                $args['placeholder'] = $option_text ?: __( 'Choose an option', 'woocommerce' );
            }
            $custom_attributes[] = 'data-allow_clear="true"';
        }
        $options .= '' . esc_attr($option_text) . '';
    }
    if ($group !== '-') $options .= '';
}
return preg_replace('/(?:]+>)\\K(.*)(?:<\\/option>)/s',$options, $html);}, 10, 4);