Question

In the jQuery docs regarding Deferreds, there’s this example of returning ajax args including jqXHR:

$.when( $.ajax("test.php") ).then(function(ajaxArgs){ 
    alert(ajaxArgs[1]); /* ajaxArgs is [ "success", statusText, jqXHR ] */
});

But it seems that the docs are wrong. ajaxArgs is actually the response from the $.ajax call.

I need to get access to the jqXHR object because I need some meta data about the actual call, but it seems to be pretty hackish. This is what I’m currently doing, but there’s got to be a better way (crossing my fingers).

xhr = $.ajax({
    'url': src,
}).done(function () {
    var meta = xhr.getResponseHeader(...);
});

What’s the best/easiest way to get access to the jqXHR data that I need?

Answer 1

Use the third argument:

.then(function(text,status,xhr) {
   var meta = xhr.getResponseHeader(...);
});

Note however that if you pass multiple deferreds into $.when, it’l be the 3rd index of the first argument, second, or third depending on which request you want the headers of.

$.when( $.ajax("test.php"),$.ajax("test.php"),$.ajax("test.php") ).then(function(){ 
    var meta1 = arguments[0][2].getResponseHeader(...);
    var meta2 = arguments[1][2].getResponseHeader(...);
    var meta3 = arguments[2][2].getResponseHeader(...);
});