How do I add a simple jQuery script to WordPress?

Question

I read the Codex and a few blog posts about using jQuery in WordPress, and its very frustrating. I've got as far as loading jQuery in functions.php file, but all of the guides out there are crappy because they assume you already have a ton of WordPress experience. For instance, they say that now that I'm loading jQuery through the functions.php file, now all I have to do is load my jQuery.

How exactly do I do this? What files, specifically, do I add code to? How exactly do I add it for a single WordPress page?

Answer 1

I know what you mean about the tutorials. Here's how I do it:

First you need to write your script. In your theme folder create a folder called something like 'js'. Create a file in that folder for your javascript. E.g. your-script.js. Add your jQuery script to that file (you don't need <script> tags in a .js file).

Here is an example of how your jQuery script (in wp-content/themes/your-theme/js/your-scrript.js) might look:

jQuery(document).ready(function($) {
  $('#nav a').last().addClass('last');
})

Notice that I use jQuery and not $ at the start of the function.

Ok, now open your theme's functions.php file. You'll want to use the wp_enqueue_script() function so that you can add your script whilst also telling WordPress that it relies on jQuery. Here's how to do that:

add_action( 'wp_enqueue_scripts', 'add_my_script' );
function add_my_script() {
    wp_enqueue_script(
        'your-script', // name your script so that you can attach other scripts and de-register, etc.
        get_template_directory_uri() . '/js/your-script.js', // this is the location of your script file
        array('jquery') // this array lists the scripts upon which your script depends
    );
}

Assuming that your theme has wp_head and wp_footer in the right places, this should work. Let me know if you need any more help.

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