AJAX jQuery实时评论

I've been trying to get my website to do live comments (so the comments appear without refreshing the page) using AJAX with jQuery (the rest of the code being in PHP and HTML). This is the code I have been using, however it doesen't seem to want to work - comments.php is the file which displays the comments, the $comments being variable for the comments.

<script type="text/javascript">
    var int=self.setInterval("showComments()",5000);
    function showComments(){
        $.post( "ajax_comments.php", function( data ) {
        $("#comments).html( data );
          });
    }
</script>

<script type="text/javascript">
    var int=self.setInterval(showComments,5000);
    function showComments() {
        $.post( "ajax_comments.php", function( data ) {
          $("#comments").html( data );
        });
    }
</script>

https://developer.mozilla.org/en-US/docs/Web/API/WindowOrWorkerGlobalScope/setInterval

In the setInterval function the first parameter should be a reference to the function, not a string with the name of the function. The string gets executed using the eval() function, which is not recommended and even though it might not be a problem here it is simply best to avoid.