$.ajax({
                        url:"http://www.imooc.com/data/check.php",
                        data: { num: $("#txtNumber").val() },
                        dataType:"text",
                        type:"post",
                        success: function (data) {
                            $("ul").append("<li>你输入的<b>  "
                            + $("#txtNumber").val() + " </b>是<b> "
                            + data + " </b></li>");
                        }
                    });