"If" conditional not working on google event tracker function

Hi guys,

I was looking at an old post on Google Analytics event tracking (https://kriesi.at/support/topic/please-clear-this-up-for-em-ga-tracking-2/), and tried to replicate it on my website.

Here is the code :

function add_custom_script(){
if(is_page(array(23)){
?>
<script>
(function($){
    $(window).load(function() {
    	 $('.button-1 a').on('click', function() {
             ga('send', 'event', 'button', 'click', 'button-1');
         });
    });
})(jQuery);
</script>
<?php
}
}
add_action('wp_footer', 'add_custom_script');

The enfold editor tells me that ther is a syntax error with the “if” conditionnal.
When I delete the “If” conditional the whole thing works, but I need the “if” conditional to use this script only on one page…
Could you guys help me please ?