我想实现一个下拉加载评论列表，现在功能已经实现，但点赞功能一直取不到动态html的内容，

请各位高手帮忙看一下 

function getComments() {
            var str = "";
            $.ajax({
                url: "/m/comment/index?pageIndex=" + pageIndex + "&pageSize=" + 10,
                type: "post",
                success: function (data) {
                    $.each(data, function (item) {
                        str += "<section class='sec' data-id='" + data[item]["ID"] + "'><dl>";
                        str += "<dt class='c_head'><img src='" + data[item]["Photo"] + "'/></dt>";
                        str += "<dd class='c_detail'><div class='c_info'>";
                        str += "<span class='c_name'>" + data[item]["NickName"] + "</span>";
                        str += "<a class='c_zan' href='javascript:InsertPraise(\"" + data[item]["ID"] + "\")'><i  class='zan'></i><span  class='zan_n'>" + data[item]["PraiseCount"] + "</span></a></div>";
                        str += "<p>" + data[item]["Comment"] + "</p></dd></dl>";
                        str += "<div class='c_time'>" + data[item]["CreateDate"] + "</div></section>";
                    });
                    $(".c_content").append(str);
                    pageIndex++;
                }
            });
            myScroll.refresh();

}

        function InsertPraise(id) {
   
           //这是获取点赞span标签的方法
                    var prais1 = $(".sec").find("[data-id='" + id + "']").find("span[class='zan_n']");
        }