Welcartの必須を設定する＆必須のアスタリスクをつける

/**
 * マンション名・部屋番号入力チェック
 */
function ag_usces_filter_customer_check($mes)
{
$address3 = $_POST["customer"]["address3"];
if(WCUtils::is_blank($address3)) {
	$mes .= "部屋番号を入力してください。<br />";
}
	return $mes;
}
add_filter('usces_filter_customer_check', 'ag_usces_filter_customer_check', 10);

/*別の配送先を指定された場合*/

function ag_usces_filter_customer_check2($mes) {
    if ( isset($_POST['delivery']['delivery_flag']) && $_POST['delivery']['delivery_flag'] == 1 ) {
        if (  WCUtils::is_blank($_POST["delivery"]["address3"]) ){
            $mes .= "部屋番号を入力してください。<br />";
        }
        return $mes;
    }
}

add_filter('usces_filter_delivery_check', 'ag_usces_filter_customer_check2', 10);


add_action('usces_action_essential_mark','my_action_essential_mark',10,2);
function my_action_essential_mark($data,$field) {
	global $usces_essential_mark;
	$essential = array('address3');
	if(in_array($field,$essential)){
		$usces_essential_mark[$field] = '<em>＊</em>';
	}
}