Stock Web Application and example controller

ErrorsController.cs

using Microsoft.ApplicationInsights;
using System;
using System.Diagnostics;
using System.Net.Http;
using System.Threading;
using System.Threading.Tasks;
using System.Web.Mvc;

namespace StockWebApp.Controllers
{
    public class ErrorsController : Controller
    {
        private static int _request;
        private static int _magicalNumber = 0;

        public ActionResult Index()
        {
            return View();
        }

        public ActionResult Random()
        {
            Interlocked.Increment(ref _request);
            if (_request > 100)
            {
                _request = 0;

                // The world best algorithm in action!
                _magicalNumber = 0;
                for (int i = 0; i < 10; i++)
                {
                    for (int j = i; j < 20; j++)
                    {
                        if (i % 3 == 0)
                        {
                            _magicalNumber++;
                        }
                        else if (j < 4)
                        {
                            _magicalNumber--;
                        }
                    }
                }

                // We're exploding but who knows the value of "magicalNumber"?
                throw new ApplicationException("This is random issue");
            }
            return View(_magicalNumber);
        }
    }
}