下载页面之前如何获取本地存储

我为一些附加内容添加了本地存储代码。这里的问题是，它在加载页面后带来了存储空间，我希望有一种方法可以使其更快并在加载页面之前执行并感谢您的帮助。

var myDirection = 'rtl';

setTimeout(function(){
if (localStorage.getItem("BlogLangAr") !== null){
BlogLang = localStorage.getItem("BlogLangAr");
myDirection = localStorage.getItem("BlogLangDir");
BlogDirection = localStorage.getItem("BlogLangDir");
$('html').attr('lang',localStorage.getItem("BlogLangAr")).attr('dir',localStorage.getItem("BlogLangDir"));
$('body').removeClass('ltr').addClass(localStorage.getItem("BlogLangDir"));
}

if (localStorage.getItem("BlogLangEn") !== null){
BlogLang = localStorage.getItem("BlogLangEn");
myDirection = localStorage.getItem("BlogLangDir");
BlogDirection = localStorage.getItem("BlogLangDir");
$('html').attr('lang',localStorage.getItem("BlogLangEn")).attr('dir',localStorage.getItem("BlogLangDir"));
$('body').removeClass('rtl').addClass(localStorage.getItem("BlogLangDir"));
}

if (localStorage.getItem("BlogLangFr") !== null){
BlogLang = localStorage.getItem("BlogLangFr");
myDirection = localStorage.getItem("BlogLangDir");
BlogDirection = localStorage.getItem("BlogLangDir");
$('html').attr('lang',localStorage.getItem("BlogLangFr")).attr('dir',localStorage.getItem("BlogLangDir"));
$('body').removeClass('rtl').addClass(localStorage.getItem("BlogLangDir"));
}

if (localStorage.getItem("BlogLangDe") !== null){
BlogLang = localStorage.getItem("BlogLangDe");
myDirection = localStorage.getItem("BlogLangDir");
BlogDirection = localStorage.getItem("BlogLangDir");
$('html').attr('lang',localStorage.getItem("BlogLangDe")).attr('dir',localStorage.getItem("BlogLangDir"));
$('body').removeClass('rtl').addClass(localStorage.getItem("BlogLangDir"));
}
},0);