localStorage 存數組

localStorage 只能直接存儲字符串，若想存儲數組，得用JSON換格式

localStorage.setItem("application", JSON.stringify(application));
var applicationItem = JSON.parse(localStorage.getItem("application"));

localStorage.setItem("key","value");                   // 存儲變量名爲key，值爲value的變量
localStorage.key = "value"                             // 同setItem方法，存儲數據
var valueLocal = localStorage.getItem("key");          // 讀取存儲變量名爲key的值
var valueLocal = localStorage.key;                     // 同getItem，讀取數據
localStorage.removeItem('key');                        // removeItem方法，刪除變量名爲key的存儲變量
localStorage.clear();                                  // clear方法，清除所有保存的數據