Newtonsoft.Json反序列化 转成Json字符串

DataTable newTable = new DataTable();
            newTable.Columns.Add("Hour");
            newTable.Columns.Add("PV");
            newTable.Columns.Add("IP", typeof(int));
            newTable.Columns["PV"].DataType = typeof(int);//指定类型
            newTable.Rows.Add("01:00", "2", "21");
            newTable.Rows.Add("02:00", "4", "10");

int[] Arr = { 0, 1 };
            List<string> list = new List<string>() { "PV", "IP" };
            string[] name = { "今日PV", "今日IP" };
            var json = new {
                categories = newTable.Rows.Cast<DataRow>().Select(u => u[0]),
                series = Arr.Select(u => new {
                    name = name[u],
                    data = newTable.Rows.Cast<DataRow>().Select(row => new { name = row[0], y = row[list[u]] }),
                }),
                chartOptions = new {
                    title = new { text = "" },
                    xAxis = new {
                        showFirstLabel = true,
                        showLastLabel = true,
                        tickmarkPlacement = "on"
                    },
                    yAxis = new {
                        title = new { enabled = false },
                        name = "网站数据"
                    },
                    plotOptions = new { series = new { marker = new { enabled = false } } },
                    credits = new { text = "" }
                }
            };
            string str_ = JsonConvert.SerializeObject(json);

{

"categories":["02:00","01:00"],
 "series":[{"name":"今日PV","data":[{"name":"02:00","y":"4"},{"name":"01:00","y":"2"}]},{"name":"今日IP","data":[{"name":"02:00","y":"10"},{"name":"01:00","y":"21"}]}],
 "chartOptions":{"title":{"text":""},"xAxis":{"showFirstLabel":true,"showLastLabel":true,"tickmarkPlacement":"on"},"yAxis":{"title":{"enabled":false},"name":"网站数据"},"plotOptions":{"series":{"marker":{"enabled":false}}},"credits":{"text":""}}

}