这段ajax错在哪？本人小白刚接触

 <script>
            function sub()
            {
            console.log($("#sub_form").serialize());
            $.ajax({
                    type:"POST",
                    datatype:"html",
                    url:"./test2.php",
                    data:
                       $('#sub_form').serialize(),
                    success:function(data){
                        console.log(data);
                        alert(data.status + "  " + data.statusText);
                    },
                    error:function(data){
                        console.log(data);
                        alert(data.status + "  " + data.statusText);
                    }
                    });
            }
        </script>

    function sub() {
        console.log($("#sub_form").serialize());
        $.ajax({
            type: "POST",
            dataType: "html",//注意大小写
            url: "./test2.php",
            data:
               $('#sub_form').serialize(),
            success: function (data) {
                console.log(data);//data是返回的字符串内容，没有status和statusText属性
                //alert(data.status + "  " + data.statusText);
            },
            error: function (data) {
                console.log(data);
                alert('error:'+data.status + "  " + data.statusText);
            }
        });
    }

var num = $("#num").val();
var name = $("#name").val();
$.ajax({
type:"post",
url:"scanning_insert2.do",
contentType:"application/x-www-form-urlencoded; charset=utf-8",
data: "num="+num+"&name="+name,
success: function(data){
if(data.flag==1) {
alert("添加成功");
location.href = "findphone.do";
} else if(data.flag==0) {
alert("添加失败");
} else{
alert("出错");
}
}
}
);