ASP.NET

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using System.Data.SqlClient;
using Microsoft.JSInterop.Infrastructure;
using Microsoft.AspNetCore.Hosting.Server;
using System.Threading.Tasks;


namespace AirHeaterControlSystem.Models
{
    public class Measurement
    {
        public string Timestamp { get; set;}
        public string MeasurementValue { get; set; }
        public string ControlValue { get; set; }

        public List<Measurement> GetMeasurementParameters()
        {
            List<Measurement> measurmentParameterList = new List<Measurement>();
            string connectionString = "DATA SOURCE=LAPTOP-1T8PALVT\\CITADEL;UID=LAPTOP-1T8PALVT\\AdisP;DATABASE=MEASUREMENTDATA;Integrated Security = True;" ;
            SqlConnection con = new SqlConnection(connectionString);
            string sqlQuery = "Select Timestamp,MeasurementValue,ControlValue from MEASUREMENTDATA";
            con.Open();

            SqlCommand cmd = new SqlCommand(sqlQuery, con);

            SqlDataReader dr = cmd.ExecuteReader();

            if (dr != null)
            {
                while (dr.Read())
                {
                    /*Measurement ChartValues = new Measurement();
                    ChartValues.ChartYvalue= Convert.ToDouble(dr[])*/

                    
                    Measurement measurementParameter = new Measurement();
                    
                    measurementParameter.Timestamp = dr["TimeStamp"].ToString();

                    measurementParameter.MeasurementValue = dr["MeasurementValue"].ToString();
                    measurementParameter.ControlValue = dr["ControlValue"].ToString();

                    measurmentParameterList.Add(measurementParameter);                  

                }
            }

            return measurmentParameterList;       
        }

    }
}

@page
@model AirHeaterControlSystem.Pages.MeasurementModel
@{
    ViewData["Title"] = "Measurement Parameters";


}
<div>

    <h1> Airheater temperature measurement</h1>

    <table class="table">
        <thead>
            <tr>
                <th>Timestamp</th>
                <th>MeasurementValue</th>
                <th>ControlValue</th>
            </tr>
        </thead>
        <tbody>
            @foreach (var measurement in Model.measurmentParameterList)
            {
                <tr>
                    <td> "measurement.Timestamp</td>
                    <td> "measurement.MeasurementValue</td>
                    <td> "measurement.ControlValue</td>

                </tr>

            }
        </tbody>

    </table>
</div>

public class City
{
        public int Id { get; set; }        
        public string CityName { get; set; }
        public virtual List<Zone> Zones { get; set; } = new List<Zone>();
}

public class Zone
 {
        public int Id { get; set; }
        public string ZoneName { get; set; }

        public int CityId { get; set; }
        public virtual City City { get; set; }
}

public class SettingsModel
    {
        public City NewCity { get; set; }
        public List<City> CurrentCities { get; set; }
    }

<form method="post" action="/Administration/UpdateCity">
...
<input type="hidden" id="CurrentCities_0__Id" name="CurrentCities[0].Id" value="7">
<input type="text"  id="CurrentCities_0__CityName" name="CurrentCities[0].CityName" value="Austin">
...
</form>
...
<form method="post" action="/Administration/UpdateCity">
...
<input type="hidden" id="CurrentCities_1__Id" name="CurrentCities[1].Id" value="4">
<input type="text"  id="CurrentCities_1__CityName" name="CurrentCities[1].CityName" value="Dallas">
...
</form>

public IActionResult UpdateCity([Bind(Prefix = "CurrentCities")]List<City> myCity) 
{
...
}

<input type="text" id="CurrentCities_0__Zones_0__ZoneName" name="CurrentCities[0].Zones[0].ZoneName" value="Austin Metro Area">
...
<input type="text" id="CurrentCities_1__Zones_0__ZoneName" name="CurrentCities[1].Zones[0].ZoneName" value="San Antonio Metro Area">

<pre>        public List<AgendaModel> MostrarTodosCalendar()
        {
            List<AgendaModel> lista = new List<AgendaModel>();
            AgendaModel item;
            DAL objDAL = new DAL();
            string sql = "SELECT id, title, start, end, AllDay, Color, TextColor FROM agenda";
            DataTable dt = objDAL.RetDataTable(sql);

            for (int i = 0; i < dt.Rows.Count; i++)
            {
                item = new AgendaModel
                {

                    Id = dt.Rows[i]["Id"].ToString(),
                    Title = dt.Rows[i]["Title"].ToString(),
                    Start = dt.Rows[i]["Start"].ToString(),
                    End = dt.Rows[i]["End"].ToString(),
                    //AllDay = dt.Rows[i]["Allday"].ToString(),
                    Color = dt.Rows[i]["Color"].ToString(),
                    TextColor = dt.Rows[i]["TextColor"].ToString()

                };

                lista.Add(item);
            }

            return lista;
        }

function CriarEventosCalendario() {

       var events = [];


       @{
           foreach(var item in (List<AgendaModel>)ViewBag.ListaEventos)
                  {<text>events.push({
                    'id': @item.Id,
                    'title': '@item.Title',
                    'start': '@item.Start',
                    'end': '@item.End',
                    'allDay': false,
                    'color': '@item.Color',
                    'textColor': '@item.TextColor'
                  });</text>

           }

       }

I want to convert to JSON because fullcalendar is not showing the data as it currently is.

var result = CreatedAtRoute("GetOrder", new { order.Id }, order);
return Ok(result);

[HttpGet("GetAdminOrder/{orderId}"), Authorize(AuthenticationSchemes = AuthSchemes, Policy = AuthPolicies.Admin)]
[Route("{orderId}", Name = "GetOrder")]        
public async Task<GetAdminOrder> GetAdminOrder(string orderId)