将数据保存到localStorage

Question

我在将数据保存到localStorage时尝试增加键值。我知道我可以通过闭包来做到这一点，但我在JS中很新鲜，不知道我怎么做。

(function() {
  window.onload = function() {
    document.getElementById('buttonCreate').onclick = function() {
      var topicValue = document.getElementById("create-topic").value;
      var statusValue = document.getElementById("create-status").value;
      var descriptionValue = document.getElementById("create-description").value;
      var storage = new Storage();
      var ticket = {
        topic: topicValue,
        status: statusValue,
        description: descriptionValue
      };
      storage.set("Item", ticket);
    }
  }
})();

function Storage() {
  this._ITEMS_DESCRIPTOR = 'items';
}
Storage.prototype.get = function() {
  var fromStorage = localStorage.getItem(this._ITEMS_DESCRIPTOR);
  return fromStorage ? JSON.parse(fromStorage) : [];
};
Storage.prototype.set = function(key, items) {
  localStorage.setItem(key, JSON.stringify(items));
};