jQuery ajax在前台如何避免后台返回的json数据

jQuery ajax在前台如何处理后台返回的json数据
功能是用asp.net +jQuery ajax+WebServices实现的    我在后台的webmethod方法中将DataSet转化为json  并将json以string的方式返回到前台
json如下：
                        "{\"ok\":true,
                        "ds\":[{\"OrderNo\":\"asdfsdf\",
                        "EmployeeWw\":\"sadfdsf\",
                        "Data\":\"2014-6-3\",
                        "CustomerWw\":\"sdfsadf\",
                        "OrderAttribute\":\"啊啊啊啊啊啊啊啊啊啊啊啊啊啊\",
                        "OrderCount\":\"3\",
                        "OrderMoney\":\"235.00\",
                        "buyertype\":\"True\",
                        "OrderStatus\":\"False\"}]}"

红色部分代码的意思是ds不为空，
下面附上DataSet转json的类：
 

public class DataSetToJSON

    {

        /// <summary>

        /// 将DataSet数据转化为json格式

        /// </summary>

        /// <param name="ds"></param>

        /// <returns></returns>

        public string GetDatasetToJson(DataSet ds)

        {

            if (ds == null || ds.Tables.Count <= 0 || ds.Tables[0].Rows.Count <= 0)

            {

                //如果查询到的数据为空则返回标记ok:false

                return "{\"ok\":false}";

            }

            StringBuilder sb = new StringBuilder();

            sb.Append("{\"ok\":true,");

            foreach (DataTable dt in ds.Tables)

            {

                sb.Append(string.Format("\"{0}\":[", dt.TableName));

                foreach (DataRow dr in dt.Rows)

                {

                    sb.Append("{");

                    for (int i = 0; i < dr.Table.Columns.Count; i++)

                    {

                        sb.AppendFormat("\"{0}\":\"{1}\",", dr.Table.Columns[i].ColumnName.Replace("\"", "\\\"").Replace("\'", "\\\'"), ObjToStr(dr[i]).Replace("\"", "\\\"").Replace("\'", "\\\'")).Replace(Convert.ToString((char)13), "\\r\\n").Replace(Convert.ToString((char)10), "\\r\\n");

                    }

                    sb.Remove(sb.ToString().LastIndexOf(','), 1);

                    sb.Append("},");

                }

                sb.Remove(sb.ToString().LastIndexOf(','), 1);

                sb.Append("],");

            }

            sb.Remove(sb.ToString().LastIndexOf(','), 1);