时间字符串生成小标签

javascript:(function() {
  const now = new Date();
  const year = now.getFullYear().toString().substr(-2);
  const month = ('0' + (now.getMonth() + 1)).slice(-2);
  const day = ('0' + now.getDate()).slice(-2);
  const hours = ('0' + now.getHours()).slice(-2);
  const minutes = ('0' + now.getMinutes()).slice(-2);
  const seconds = ('0' + now.getSeconds()).slice(-2);
  const code = year + month + day + hours + minutes + seconds;
  const el = document.createElement('textarea');
  el.value = code;
  el.setAttribute('readonly', '');
  el.style.position = 'absolute';
  el.style.left = '-9999px';
  document.body.appendChild(el);
  el.select();
  document.execCommand('copy');
  document.body.removeChild(el);
  alert('已将时间字符串复制到剪贴板中：' + code);
})();

格式是 YYMMDDhhmmss。