vue项目如何监听localStorage或sessionStorage的变化

/**
 * @description
 * @author (Set the text for this tag by adding docthis.authorName to your settings file.)
 * @date 2019-05-29
 * @param { number } type 1 localStorage 2 sessionStorage
 * @param { string } key 键
 * @param { string } data 要存储的数据
 * @returns 
 */
Vue.prototype.$addStorageEvent = function (type, key, data) {
  if (type === 1) {
    // 创建一个StorageEvent事件
    var newStorageEvent = document.createEvent('StorageEvent');
    const storage = {
      setItem: function (k, val) {
        localStorage.setItem(k, val);
        // 初始化创建的事件
        newStorageEvent.initStorageEvent('setItem', false, false, k, null, val, null, null);
        // 派发对象
        window.dispatchEvent(newStorageEvent);
      }
    }
    return storage.setItem(key, data);
  } else {
    // 创建一个StorageEvent事件
    var newStorageEvent = document.createEvent('StorageEvent');
    const storage = {
      setItem: function (k, val) {
        sessionStorage.setItem(k, val);
        // 初始化创建的事件
        newStorageEvent.initStorageEvent('setItem', false, false, k, null, val, null, null);
        // 派发对象
        window.dispatchEvent(newStorageEvent);
      }
    }
    return storage.setItem(key, data);
  }
}

this.$addStorageEvent(2, "user_info", data);

this.resetSetItem('watchStorage', jsonObj);

window.addEventListener('setItem', (e) => {
   console.log(e);
});

window.addEventListener('setItem', ()=> {
    this.newVal = sessionStorage.getItem('watchStorage');
    var data=JSON.parse(this.newVal)
     console.log(data)
})