AJAX通话永无止境

I have an ajax call on my index.php page that displays contents spit out by a controller. It sends information an a link click to itself and the content is displayed, the content is a list of the directories and files. It works great on the first click and shows the contents of the directory you clicked but when I click on the newly created link to show its content it runs forever and does not stop. Is there something wrong with my AJAX?

here is the AJAX it sends a couple variables each time:

<script>
    var parent_dirs = "";
    var click_count = 0;

    jQuery('.container').on('click', '.show_content', function(e)
    {
        e.preventDefault();

        alert('called');
        var href = jQuery(this).attr('href');
        parent_dirs += jQuery(this).attr('id');
        click_count++;

        jQuery.ajax({
            url : "/",
            type: "POST",
            data : { link: href, parent: parent_dirs, click_count: click_count },
            success: function(data)
            {
                var result = jQuery(data).find('.content_result');    
                jQuery('.container').append(result);
            },
            error: function(thrownError)
            {
                console.log(thrownError);
            }
        });
    });
</script>

and here is the index.php page I can not figure out why it runs nonstop. I figured it would just update the $_POST variables below and would run like before:

include "../app/bootstrap.php";
include "../src/controllers/DisplayContentsController.php";

$link = (isset($_POST['link']) ? $_POST['link'] : null);
$parent = (isset($_POST['parent']) ? $_POST['parent'] : null);
$click_count = (isset($_POST['click_count']) ? $_POST['click_count'] : null);

if ($link != null)
{
    if($click_count == 1)
    {
        $full_path = $starting_file_path . '/' . $parent . $link;
    }
    else
    {
        $full_path = $starting_file_path . '/' . $link;
    }

    DisplayContentsController::show($twig, $starting_file_path . '/' . $link);
}
else
{
    DisplayContentsController::show($twig, $starting_file_path);
}