Question

I’m trying to make getJSON to use JSONP object, but I can’t figure out how to build the url:

for instance: http://graph.facebook.com/?ids=http://legrandj.eu/article/blouse_ghost_dream

where and how should I add “callback=?” parameter?

thank you

d.

Answer 1

Append &callback=? to the URL.

$.getJSON('http://graph.facebook.com/?ids=http://legrandj.eu/article/blouse_ghost_dream&callback=?', function(data) {
    // ..
});
// Or (more clean): 
$.getJSON('http://graph.facebook.com/?callback=?',
    {
        ids: 'http://legrandj.eu/article/blouse_ghost_dream'
    },
    function(data) {
        // ...
    }
);

Given this code, jQuery creates and inserts a <script src="http://graph.facebook.com/?ids=http://legrandj.eu/article/blouse_ghost_dream&callback=jQuery171022388557461090386_1332329918803&_=133232991983">. Explanation of the URL:

• Base URL: http://graph.facebook.com/?ids=http://legrandj.eu/article/blouse_ghost_dream
• Callback handler: &callback=jQuery171022388557461090386_1332329918803
  jQuery replaces ? in callback=? with an unique temporary identifier.
• Cache-breaking: &_=133232991983

The FB API returns a response in the following format (JSONP):

/**/ jQuery171022388557461090386_1332329918803({
   "http://legrandj.eu/article/blouse_ghost_dream": {
      "id": "http://legrandj.eu/article/blouse_ghost_dream",
      "shares": 3
   }
});

Since this is included by the <script> tag, a function jQuery171022388557461090386_1332329918803 is called, passing the parsed JSON as an argument. The parsed JSON is then passed to the function which you defined in jQuery.getJSON.