Js：将按钮ID传递给同一页面

<script type="text/javascript">
    $(document).ready(function () {
        $(".Categories").click(function () {
            var catId = $(this).attr('id');
            catId = String(catId);

            jQuery.ajax({
                url: "index.php",
                data: { catId },
                type: "POST",
                success: function (data) {
                    $("#categoryField").html(data);
                }
            });
        });
    });
</script>
<script type="text/javascript">
    $(document)