{"success":"true","msg":"","data":[{"macName":"正面预拼装机","state":1.0},{"macName":"正面拼板压力架","state":1.0},{"macName":"板片翻身系统","state":1.0},{"macName":"反面预拼装机","state":1.0},{"macName":"反面拼板压力架","state":1.0},{"macName":"划线喷码机","state":0.0},{"macName":"纵骨焊接安装辊道","state":0.0},{"macName":"纵骨焊接机","state":1.0},{"macName":"T排焊接安装辊道","state":0.0}]}

     public class MacState

     {

         /// <summary>

         /// 请求状态

         /// </summary>

         public string success { get; set; }

         /// <summary>

         /// 错误信息

         /// </summary>

         public string msg { get; set; }

         /// <summary>

         /// JSON数组

         /// </summary>

         public List<MacStateData> data { get; set; }

     }

     public class MacStateData

     {

         /// <summary>

         /// 设备名称

         /// </summary>

         public string macName { get; set; }

         /// <summary>

         /// 运行状态 运行/停止（1/0）

         /// </summary>

         public decimal state { get; set; }

     }

     /// <summary>

     /// 设备状态情况

     /// </summary>

     /// <returns>JSON数组</returns>

     [WebMethod(Description ="设备状态")]

     public string GetMacState()

     {

         MacState obj = new MacState();

         try

         {

             DateTime NowDate = DateTime.Now;

             DataTable dt_his_count = new DataTable();

             DataTable dt_mac_state = new DataTable();

             int max_count = ;

             string add_his_sql = "INSERT INTO EMES_MAC_STATE_PORT_HIS (DEF_DATE) VALUES (TO_DATE('{0}','YYYY-MM-DD HH24:MI:SS'))";

             DbUtil.ExecuteSql(string.Format(add_his_sql, NowDate));

             string query_his_sql = "SELECT COUNT(*) FROM EMES_MAC_STATE_PORT_HIS";

             dt_his_count = DbUtil.QueryDT(query_his_sql);

             if (Convert.ToDecimal(dt_his_count.Rows[][]??"")>max_count) //接口日志超过20W条，自动删除

             {

                 string del_sql = "DELETE FROM EMES_MAC_STATE_PORT_HIS";

                 DbUtil.ExecuteSql(del_sql);

             }

             string query_mac_state_sql = "SELECT MAC_NAME,STATE FROM EMES_MAC_STATE";

             dt_mac_state = DbUtil.QueryDT(query_mac_state_sql);

             if (dt_mac_state.Rows.Count > )

             {

                 obj.success = "true";

                 obj.msg = "";

                 obj.data = new List<MacStateData>(); //实例化JSON数组，不实例化要报错                

                 for (int i = ; i < dt_mac_state.Rows.Count; i++)

                 {

                     MacStateData objData = new MacStateData(); //实例化JSON数组对象，用于添加JSON数组集合

                     objData.macName = dt_mac_state.Rows[i]["MAC_NAME"].ToString();

                     objData.state = Convert.ToDecimal(dt_mac_state.Rows[i]["STATE"] ?? "");

                     obj.data.Add(objData); //添加JSON数组集合

                 }

                 string res = JsonConvert.SerializeObject(obj); //转JSON数组，演示用，下面讲方法使用

                  return JSONHelper.ToJSON(obj); //调用的封装函数，不用管，我们将上面的方式

             }

             else

             {

                 obj.success = "false";

                 obj.msg = "当前无数据信息,请稍后再试!";

                 obj.data = new List<MacStateData>();

                 return JSONHelper.ToJSON(obj);

             }

         }

         catch (Exception ex)

         {

             obj.success = "false";

             obj.msg = ex.Message;

             obj.data = new List<MacStateData>();

             return JSONHelper.ToJSON(obj);

         }

     }

 引入命名空间：

 using Newtonsoft.Json;

 方法使用：

 JsonConvert.SerializeObject(实体类对象)