Get data through JSON

//Javascript Code

<script language="javascript" type="text/javascript" src="jquery.js"></script>
<script language="javascript" type="text/javascript">
$(document).ready(function(){
$("#sample").click(function(){

  $.ajax({
      type:'GET',
      url :'testAjax.php',
      success:function(msg)
      {
        var jvar = eval('(' + msg + ')');
        alert(jvar.a);
        alert(jvar.b);
      }
  })
})
})
</script>

//Sample Div

<div id="sample" style="cursor:pointer;>here</div>


//PHP request page

<?php
$arr = array('a'=>5,'b'=>8);
$encodedVal = json_encode($arr);
echo $encodedVal;
?>