使用JSON传递数组?

我有这个PHP代码

   $ids = array(1,2,3);
   $names = array("cat","elephant","cow"); 
   $originalSettings = array ('ids'=>$ids,'names'=>$names);
   $jsonSettings = json_encode($originalSettings);
   echo $jsonSettings;

这是jquery代码

$.post("ajax.php", {},
function(data){
data.ids.each(function(i) {
alert(data.names[i]);
}
//is it possible to receive the arrays and navigate them   
}, "json");

如何使用JSON传递数组并以JavaScript接收它们?

谢谢