Kendo Grid MVC Binding Base controller class

KendoBaseController.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Kendo.Mvc.Extensions;
using Kendo.Mvc.UI;
using Microsoft.AspNetCore.Mvc;
using FiftyEggs.Data.Data;
using Microsoft.AspNetCore.Authorization;
using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.ChangeTracking;

namespace FiftyEggsSample.Controllers
{
    [Authorize]
    public class KendoBaseController<T> : Controller where T : class
    {

        internal readonly SampleContext _context;
        public Func<int?, T, bool> FilterFunc;

        public KendoBaseController(SampleContext context)
        {
            _context = context;
            FilterFunc = NoFilter;
        }
        public virtual async Task<ActionResult> Index(int? Id=null)
        {
            var cn = this.ControllerContext.RouteData.Values["controller"].ToString();
            ViewBag.Title = cn;
            ViewBag.Id = Id;
            ViewBag.ControllerName = cn;
            return View();
        }


        public KendoBaseController(SampleContext context, Func<int?, T, bool> filterFunc)
        {
            _context = context;
            FilterFunc = filterFunc;
        }

        private bool NoFilter(int? id, T thing)
        {
            return true;
        }

        public virtual async Task<ActionResult> _Read([DataSourceRequest]DataSourceRequest request, int? id = null)
        {
            var repo = _context.Set<T>();
            var records = await repo.Where(p => FilterFunc(id, p)).ToListAsync();
            return Json(records.ToDataSourceResult(request));
        }

        [HttpPost]
        public virtual async Task<ActionResult> _Create([DataSourceRequest] DataSourceRequest request, [Bind(Prefix = "models")]IEnumerable<T> records)
        {
            var results = new List<T>();
            var repo = _context.Set<T>();

            if (records != null && ModelState.IsValid)
            {
                foreach (var record in records)
                {
                    repo.Add(record);
                    results.Add(record);
                }

                TrackSave(_context.ChangeTracker);
                await _context.SaveChangesAsync();
            }
            return Json(results.ToDataSourceResult(request, ModelState));
        }

        public virtual void TrackSave(ChangeTracker contextChangeTracker)
        {
        }

        [HttpPost]
        public virtual async Task<ActionResult> _Update([DataSourceRequest] DataSourceRequest request, [Bind(Prefix = "models")]IEnumerable<T> records)
        {
            if (records != null && ModelState.IsValid)
            {
                foreach (var record in records)
                {
                    _context.Update(record);
                }
                TrackSave(_context.ChangeTracker);

                await _context.SaveChangesAsync();
            }

            return Json(records.ToDataSourceResult(request, ModelState));
        }

        [HttpPost]
        public virtual async Task<ActionResult> _Destroy([DataSourceRequest] DataSourceRequest request, [Bind(Prefix = "models")]IEnumerable<T> records)
        {
            if (records.Any())
            {
                foreach (var record in records)
                {
                    _context.Remove(record);
                }
            }
            TrackSave(_context.ChangeTracker);

            await _context.SaveChangesAsync();

            return Json(records.ToDataSourceResult(request, ModelState));
        }

        [HttpPost]
        public ActionResult Excel_Export_Save(string contentType, string base64, string fileName)
        {
            var fileContents = Convert.FromBase64String(base64);

            return File(fileContents, contentType, fileName);
        }
    }
}