how to return json in an AJAX callback in D7?

Posted by arnoldbird on June 1, 2012 at 9:03pm

How to return json?

In my js, I have...

var posturl = '/mymodule/my/callback';
$.post(posturl, {}, function(r) {
    console.log(r);
}, "json");

In my PHP...

function mymodule_page_my_callback() {

  $arr['apple'];
  $arr['banana'];
  
  drupal_json_output($arr);
// also tried: ajax_deliver($arr);
// also tried: print json_encode($arr);
// also had a look at the ajax example module but it does not use json.
  
}

In the firebug console I get a null response.

Thanks for your help.

Comments

You want

Posted by roper. on June 1, 2012 at 9:14pm

You want drupal_json_output(); it'll set the necessary header. :)

Thanks, but that's what I

Posted by arnoldbird on June 1, 2012 at 9:26pm

Thanks, but that's what I have in the code I posted. Doesn't work. I mean, doesn't seem to work. Something wrong in my js that you can see?

Oh ha! Sorry, missed that.

Posted by roper. on June 1, 2012 at 9:30pm

Oh ha! Sorry, missed that. :P

What happens when you just try to hit the page in your browser? You should see the raw JSON there... I'm assuming you have implemented hook_menu() to define your page callback right?

Ugh. Dumbest PHP mistake

Posted by arnoldbird on June 1, 2012 at 9:37pm

Ugh. Dumbest PHP mistake ever, I'm pretty sure. Look how I'm populating the $arr array. Ooops! That won't do it!

Yeah I just saw that too

Posted by roper. on June 1, 2012 at 9:39pm

Yeah I just saw that too lol... Always something simple. :)

Sure enough, it works fine

Posted by arnoldbird on June 1, 2012 at 9:39pm

Sure enough, it works fine when I fix the remedial PHP mistake.