【前端新手之路-第一天】如何实现两个标签页中的通讯？

(function()
{
    If(!sessionStorage.length)
    {//新打开的标签页，sessionStorage
        localStorage.setItem("getsessionStorage",Date().now);
        //触发storage事件，新旧页面都会监听
        window.addEventListener("storage",add);

        function add(event)
        {
            if(event.key =="getsessionStorage")
            {
                以下操作对已有页面
                localStorage.setItem("sessionStorage",JSON.stringify(sessionStorage));
                localStorage.removeItem("sessionStorage");
            }
            else if(event.key=="sessionStorage"&& !sessionStorage.length){
                var data=JSON.parse(event.newValue);
                for(var key in data){
                    sessionStorage.setItem(key,data[key]);
                }

            }
        }
        ;
    }
})()