test

HTML

<span class='localization' caption='test'>test</span>
<span class='localization' caption='name'>имя</span>
<br>
<input class='rus' type=button value='rus'>
<input class='eng' type=button value='eng'>

JavaScript

$(document).ready(function() {

   $('.rus').on('click', function() {
      var r = $('.localization').each(function() {
         var el = $(this);
         var key = (el.attr('caption'));
         el.text(rus[key]);
      });
   });


   $('.eng').on('click', function() {
      var r = $('.localization').each(function() {
         var el = $(this);
         var key = (el.attr('caption'));
         el.text(eng[key]);
      });
   });



   var rus = {
      test: 'тест',
      name: 'имя'
   };
   var eng = {
      test: 'test',
      name: 'name'
   };





});