How to make custom error pages work in ASP.NET MVC 4

Question

I want a custom error page shown for 500, 404 and 403. Here\'s what I have done:

1. Enabled custom errors in the web.config as follows:

Answer 1

Here is my solution. Use [ExportModelStateToTempData] / [ImportModelStateFromTempData] is uncomfortable in my opinion.

~/Views/Home/Error.cshtml:

@{
    ViewBag.Title = "Error";
    Layout = "~/Views/Shared/_Layout.cshtml";
}

Error




    @Html.ValidationMessage("Error")

    

    


    Go Back
    

~/Controllers/HomeController.sc:

public class HomeController : BaseController
{
    public ActionResult Index()
    {
        return View();
    }

    public ActionResult Error()
    {
        return this.View();
    }

    ...
}

~/Controllers/BaseController.sc:

public class BaseController : Controller
{
    public BaseController() { }

    protected override void OnActionExecuted(ActionExecutedContext filterContext)
    {
        if (filterContext.Result is ViewResult)
        {
            if (filterContext.Controller.TempData.ContainsKey("Error"))
            {
                var modelState = filterContext.Controller.TempData["Error"] as ModelState;
                filterContext.Controller.ViewData.ModelState.Merge(new ModelStateDictionary() { new KeyValuePair("Error", modelState) });
                filterContext.Controller.TempData.Remove("Error");
            }
        }
        if ((filterContext.Result is RedirectResult) || (filterContext.Result is RedirectToRouteResult))
        {
            if (filterContext.Controller.ViewData.ModelState.ContainsKey("Error"))
            {
                filterContext.Controller.TempData["Error"] = filterContext.Controller.ViewData.ModelState["Error"];
            }
        }

        base.OnActionExecuted(filterContext);
    }
}

~/Controllers/MyController.sc:

public class MyController : BaseController
{
    public ActionResult Index()
    {
        return View();
    }

    public ActionResult Details(int id)
    {
        if (id != 5)
        {
            ModelState.AddModelError("Error", "Specified row does not exist.");
            return RedirectToAction("Error", "Home");
        }
        else
        {
            return View("Specified row exists.");
        }
    }
}

I wish you successful projects ;-)