Using php inside javascript in wordpress

Take a look at wp_localize_script. Although ostensibly for translation, it lets you pass PHP values to JS. Here's a fairly good walkthrough on how to use it.

EDIT:

First, ensure that you are loading your JS using wp_enqueue_script, as you will need to refer to the handle. In your functions.php you'd have:

$date = get_option('director_date');wp_enqueue_script('my-script', get_stylesheet_directory_uri() . 'js/my-script.js');wp_localize_script('my-script', 'my_script_vars', array(        'date' => $date    ));

wp_localize_script takes three arguments:

1. The handle of he script to pass the variables object to. This should match the handle being used in wp_enqueue_script
2. The name of the variable object you want to create. You will use this name to refer to the object in JS
3. The array of variable to pass to the object. Here I'm just passing the $date variable we declared earlier, but you can obviously pass whatever you want.

Then in my-script.js, you'd access this object very simply:

var $date = my_scripts_vars.date;alert($date); // Or do whatever you want with it

In index.php, you can do something like:

<?php $date = get_option('director_date'); ?><script type="text/javascript">var generated_date = '<?php echo $date; ?>';</script>

Just make sure you do this before you include the JavaScript where you want to reference the generated_date variable you just created.