JS i18n

index.html

<div class="info">
	<p data-localize="_welcomeText">Herzlich willkommen!</p>
	<a href="#" data-localize="_showPDF">PDF anzeigen</a>
</div>

lang.json

{
	"en": {
			"_customer": "Customer",
			"_customers": "Customers",
			"_welcomeText": "Welcome!",
			"_showPDF": "Show PDF"
		},
	
	"de": {
			"_customer": "Kunde",
			"_customers": "Kunden",
			"_welcomeText": "Herzlich willkommen!",
			"_showPDF": "PDF anzeigen"
	}
}

language.js

function getLanguage(lang) {
	$.ajax({
		type: 'GET',
		url: 'js/lang.json',
		async: false,
		dataType: 'json',
		success: function(data) {
			if(data[lang]) {
				completeTranslate(data[lang]);
			}
			else {
				completeTranslate(data['en']);
			}
		},
		error: function(e) {
			genericFailHandler(e);
		}
	});
}

var dic = new Object();
var browserLang = window.navigator.userLanguage || window.navigator.language;
var lang = "";

function translate() {
	lang = localStorage.getItem('language') || browserLang.substr(0, 2);
	getLanguage(lang);
}

function completeTranslate(language) {
	dic = language;
	$("[data-localize]").each(function(){
		$(this).text(dic[$(this).attr('data-localize')]);
	})
}