Infinite Scrolling Using JQuery Ajax MVC C#

I have successfully loaded the first page with 20 records. I have 100,000 records to load for testing purpose. When I scroll my mouse, it won't invoke my Infinite Scroll action method in my controller.

This is my view page

@{
    ViewBag.Title = "Index";
}<div id="tblbody"><table class="table table-responsive table-striped table-bordered" id="tbldata"><thead><tr><th>ID</th><th>Name</th><th>Email</th></tr></thead><tbody id="trow">
            @{
                Html.RenderAction("table_row", "Employee", new { Model = Model });
            }</tbody></table><div id="loadingdiv" style="text-align:center;display:none;margin-bottom:20px;"><img src="~/Images/ajax-loader.gif" /></div></div>
@section scripts {<script>$(document).ready(function () {
        var pageindex = 2;
        var NoMoredata = false;
        var inProgress = false;$(window).scroll(function () {
            if ($(window).scrollTop() > Number($("#tblrow").height()) / 2 && !NoMoredata && !inProgress) {

                inProgress = true;
                $("#loadingdiv").show();$.post("@Url.Action("InfiniteScroll", "Employee")", { "pageindex": pageindex },
                    function (data) {
                        pageindex = pageindex + 1;
                        NoMoredata = data.NoMoredata;$("#trow").append(data.HTMLString);$("#loadingdiv").hide();
                        inProgress = false;
                    }
                    );
            }
        }); 
    })</script>
}

and this is my controller page.  I put a break point in this InfiniteScroll action method but it won't come to this break point as i scroll down.

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using WebApplication14.Models;
using WebApplication14.Repository;

namespace WebApplication14.Controllers
{
    public class EmployeeController : Controller
    {
        //
        // GET: /Home/
        public ActionResult Index()
        {
            int pagesize = 20;
            var rowdata = DataAccess.GetEmployee(1, pagesize);
            return View(rowdata);
        }

        protected string renderPartialViewtostring(string Viewname, object model)
        {
            if (string.IsNullOrEmpty(Viewname))

                Viewname = ControllerContext.RouteData.GetRequiredString("action");
            ViewData.Model = model;
            using (StringWriter sw = new StringWriter())
            {
                ViewEngineResult viewresult = ViewEngines.Engines.FindPartialView(ControllerContext, Viewname);
                ViewContext viewcontext = new ViewContext(ControllerContext, viewresult.View, ViewData, TempData, sw);
                viewresult.View.Render(viewcontext, sw);
                return sw.GetStringBuilder().ToString();
            }

        }

        public class JsonModel
        {
            public string HTMLString { get; set; }
            public bool NoMoredata { get; set; }
        }

        [ChildActionOnly]
        public ActionResult table_row(List<Employee> Model)
        {
            return PartialView(Model);
        }

        [HttpPost]
        public ActionResult InfiniteScroll(int pageindex)
        {
            System.Threading.Thread.Sleep(1000);
            int pagesize = 20;
            var tbrow = DataAccess.GetEmployee(pageindex, pagesize);
            JsonModel jsonmodel = new JsonModel();
            jsonmodel.NoMoredata = tbrow.Count < pagesize;
            jsonmodel.HTMLString = renderPartialViewtostring("table_row", tbrow);
            return Json(jsonmodel);
        }
    }
}