Future<String> exampleAddCookie() async {
  var name = rq.get<String>('name', def: '');
  var value = rq.get<String>('value', def: '');
  var safe = rq.get<bool>('safe', def: false);
  var action = rq.get<String>('action', def: 'add');

  if (action == 'delete') {
    // 删除 Cookie
    rq.removeCookie(name);                  
  } else if (action == 'add' && name.isNotEmpty && value.isNotEmpty) {
    // 添加 Cookie
    rq.addCookie(name, value, safe: safe);  
  }

  return exampleCookie();
}