How can we do the Error Handling in ASP.NET MVC3 Razor?

I will explain a Nice exception handling mechanism in ASP.NET MVC. Whenever the exception generate it automatically redirect to the corresponding error page that i have mentioned at end of this comment.Please Create a class and paste the below code in that class.

using System.Web;
using System.Web.Mvc;

namespace App.Web
{
  public class CustomHandleErrorAttribute : HandleErrorAttribute
  {
    public CustomHandleErrorAttribute()
    {
    }

    public override void OnException(ExceptionContext filterContext)
    {
      if (filterContext.ExceptionHandled || !filterContext.HttpContext.IsCustomErrorEnabled)
      {
        return;
      }

      if (new HttpException(null, filterContext.Exception).GetHttpCode() != 500)
      {
        return;
      }

      if (!ExceptionType.IsInstanceOfType(filterContext.Exception))
      {
        return;
      }

      // if the request is AJAX return JSON else view.
      if (filterContext.HttpContext.Request.Headers["X-Requested-With"] == "XMLHttpRequest")
      {
        filterContext.Result = new JsonResult
        {
          JsonRequestBehavior = JsonRequestBehavior.AllowGet,
          Data = new
          {
            error = true,
            message = filterContext.Exception.Message
          }
        };
      }
      else
      {
        var controllerName = (string)filterContext.RouteData.Values["controller"];
        var actionName = (string)filterContext.RouteData.Values["action"];
        var model = new HandleErrorInfo(filterContext.Exception, controllerName, actionName);

        filterContext.Result = new ViewResult
        {
          ViewName = View,
          MasterName = Master,
          ViewData = new ViewDataDictionary<HandleErrorInfo>(model),
          TempData = filterContext.Controller.TempData
        };
      }
      filterContext.ExceptionHandled = true;
      filterContext.HttpContext.Response.Clear();
      filterContext.HttpContext.Response.StatusCode = 500;

      filterContext.HttpContext.Response.TrySkipIisCustomErrors = true;
    }
  }
}

and then put the below code in Global.asax.cs

protected void Application_Error(object sender, EventArgs e)
       {
           var httpContext = ((MvcApplication)sender).Context;
           var currentController = " ";
           var currentAction = " ";
           var currentRouteData = RouteTable.Routes.GetRouteData(new HttpContextWrapper(httpContext));

           if (currentRouteData != null)
           {
               if (currentRouteData.Values["controller"] != null && !String.IsNullOrEmpty(currentRouteData.Values["controller"].ToString()))
               {
                   currentController = currentRouteData.Values["controller"].ToString();
               }

               if (currentRouteData.Values["action"] != null && !String.IsNullOrEmpty(currentRouteData.Values["action"].ToString()))
               {
                   currentAction = currentRouteData.Values["action"].ToString();
               }
           }

           var ex = Server.GetLastError();
           var controller = new ErrorController();
           var routeData = new RouteData();
           var action = "Index";

           if (ex is HttpException)
           {
               var httpEx = ex as HttpException;

               switch (httpEx.GetHttpCode())
               {
                   case 404:
                       action = "NotFound";
                       break;

                   case 401:
                       action = "AccessDenied";
                       break;
               }
           }

           httpContext.ClearError();
           httpContext.Response.Clear();
           httpContext.Response.StatusCode = ex is HttpException ? ((HttpException)ex).GetHttpCode() : 500;
           httpContext.Response.TrySkipIisCustomErrors = true;

           routeData.Values["controller"] = "Error";
           routeData.Values["action"] = action;

           controller.ViewData.Model = new HandleErrorInfo(ex, currentController, currentAction);
           ((IController)controller).Execute(new RequestContext(new HttpContextWrapper(httpContext), routeData));
       }

and then Create a Controller for Catching the error like below

public class ErrorController : Controller
    {
        public ActionResult Index()
        {
            var error = ViewData.Model;
            return View(error);
        }

        public ActionResult NotFound()
        {
            var error = ViewData.Model;
            return View(error);
        }

        public ActionResult AccessDenied()
        {
            var error = ViewData.Model;
            return View(error);
        }
    }

and then Create 3 views such as error.cshtml,NotFound.cshtml,AccessDenied.cshtml and paste the below mark up in each view or create a partial view for that and call in to each view. These three views are return the same model.
for example

<div><b>Controller:</b> @Model.ControllerName</div>
<div><b>Action Name :</b> @Model.ActionName</div>
<div><b>Exception:</b> @Model.Exception.Message</div>
<a href="#" style="color:Blue" id="clickMore">Click here to see more details</a>
<div id="moreDetails">
<div><b>Stack Trace:</b> @Model.Exception.StackTrace</div>
<div><b>Inner Exception:</b> @Model.Exception.InnerException</div>
</div>