SATE-EasyReceipt/app/Codes/FourSMessage/SendingStatus.php

<?php

namespace App\Codes\FourSMessage;

/**
 * 送信状態
 */
enum SendingStatus: string
{
    case NONE = '';
    case SENDING = '10'; // 送信中
    case DONE = '20'; // 送信済
}