jQuery browser detection?

Question

Is there a good way to detect if the user's browser is Internet Explorer using jQuery?

I have an issue with PNG graphics using IE and want to swap them for GIF's only if the user is viewing the site with IE.

Answer 1

You can using $.browser, yes, but it's a bad idea to use browser detection:

if($.browser.msie) { /* IE */ }

A better option for instance would be $.support which is feature detection, like this:

if(!$.support.opacity) { /* IE 6-8 */ }

$.support.opacity is false in browsers that don't support opacity in styling (though IE 7-8 handle transparent PNGs file, so this still isn't ideal, depending on what you're after...personally I think you'd be giving IE 7/8 users a sub-optimal experience).

What you should really do is target IE6 which doesn't support transparent PNGs (without an alpha filter), like this:

<!--[if IE 6]>
  <link rel="stylesheet" type="text/css" href="IE6ImageStyles.css">
<![endif]-->

Answer 2

Yes, you can, but they prefer you to use jQuery.support: http://api.jquery.com/jQuery.support/.

In this case, use jQuery.support.opacity.

Edit: assuming this is about opacity, of course.