WordPress - Enqueue scripts for only if LT IE 9

Question

In a WordPress theme, how do you conditionally include scripts for ie8 and below? This is primarily to apply polyfills for various html5/css3 features. I see that wp has the $is_IE variable which can be used as a conditional to only include scripts for IE. Is there a way to add the script for only certain versions of IE though rather than all of them? This is simple with some HTML ie conditional comments, but I'd like to include the scripts all in the same place in my functions file.

Conditional for specific versions in HTML:

<!--[if lt IE 9]> <script src="iepolyfill.min.js"></script> <![endif]-->

Conditional for all IE in WP:

    global $is_IE;

    if ( $is_IE ) {
        wp_enqueue_script( 'iepolyfill', bloginfo('stylesheet_directory').'/js/iepolyfill.min.js' );
    }

I've looked around and mainly find details about conditional scripts for wp backend only.

Any suggestions?

Answer 1

As wordpress is a PHP script, it can access server variable via $_SERVER

Then you can search for detect browser with PHP, PHP: If internet explorer 6, 7, 8 , or 9