How to return PHP variables on success AJAX/jQuery POST

Question

How do I use AJAX to return a variable in PHP? I am currently using echo in my controller to display a price on dropdown .change in a div called pr

Answer 1

echo json_encode($RESPONDE);
exit(); 

The exit is not to display other things except answer. RESPONDE is good to be array or object. You can access it at

success: function(data)
             { data }

data is the responde array or whatever you echo.. For example...

echo json_encode(array('some_key'=>'yesss')); exit();

at jquery

success: function(data){ alert(data.some_key); }