Comments on: Detect AJAX Requests using the x-requested-with header and xmlhttprequest

By: kn33ch41

kn33ch41 — Sun, 13 Mar 2011 00:56:57 +0000

@Rob

The second condition takes care of that. If the variable passed to strtolower() is empty it certainly will not equal xmlhttprequest, which means the whole statement will return false. I know you’re doing it that way to avoid throwing a notice, but this would then be a good time to use the @-operator.

strtolower(@$_SERVER['HTTP_X_REQUESTED_WITH']) == ‘xmlhttprequest’

By: Alison Harper

Alison Harper — Tue, 18 Jan 2011 06:27:36 +0000

Nice website and a cool trick

By: Rob

Rob — Tue, 04 Jan 2011 19:29:31 +0000

@kn33ch41 I'd personally say it's needed as HTTP_X_REQUESTED_WITH may not always be available and could create errors.

By: kn33ch41

kn33ch41 — Tue, 04 Jan 2011 03:54:31 +0000

isset($_SERVER['HTTP_X_REQUESTED_WITH']) is unnecessary. You might as well make the code shorter.

By: Stephen

Stephen — Wed, 29 Sep 2010 13:55:17 +0000

@Rob Thanks You too.

By: Rob

Rob — Tue, 14 Sep 2010 17:41:47 +0000

@Stephen Hi Stephen, Thanks for the comment. The -Requested-With was soemthing I accidentally came across by chance, but is REALLY useful. Nice blog you have there. BTW

By: Stephen

Stephen — Tue, 14 Sep 2010 14:40:43 +0000

I was injecting a hidden POST value to identify AJAX requests, but this is much better. I noticed the X-Requested-With header while using Firebug today.

Dear readers: I highly recommend using that second snippet to simplify your “dual-mode” scripts. Place the define line in your “bootstrap” file or in some other include that runs during every request. Then use the “if” block to switch between “rendering” modes. (JSON vs HTML)

If your readers need help finding a real-world use for this, send them to http://sholsinger.com/archive/2009/08/gracefully-degrading-ajax-php-jquery/ where I have written about using this type of method for a simple–gracefully degrading–newsletter sign-up form.

By: Rob

Rob — Fri, 26 Mar 2010 17:29:44 +0000

Cheers

Edited that code now.

By: Jay Gilford

Jay Gilford — Fri, 26 Mar 2010 16:31:48 +0000

Nice website and a cool trick
One thing I did notice is you have an apostrophe in this line
if(‘IS_AJAX_REQUEST) {
which shouldn’t be there

Regards

Jay

By: Rob

Rob — Fri, 26 Mar 2010 16:10:40 +0000

The article above edescribes how to detect requests coming from an AJAX action directly. I could submit a form using POST or via AJAX. The header I suggest allows you to isolate each type of request seperately.