Monday

MVC Custom Error: How to implement custom error pages using MVC

Introduction

Custom Error pages can make your MVC application more elegant and informative. I often see many developers more struggles for hours to implement this functionality in ASP.Net MVC application. I’ll throw full light on all aspects how to implement MVC custom error pages. I have here demonstrated very common errors of MVC application as listed below:
  • Not Found: Whenever page is not founmd (MVC 404 Page).
  • Access Denied: Whenever we are trying to access folder (CAS Code Access Security) permissions or someone like same.
  • Internal Server Error: This error is related to internal server error. 
  • Error Occurred: If any other error occurred in our MVC application.
MVC custom error page
MVC custom error page
You may conquers this example very easily, if once you go through also this example because it is extended from the earlier example. If you are already regular reader of Technology Crowds then it is OK.
You may also track Exception code and refer to custom page error in your ASP.Net MVC application.
Namespace Used:

using System.Web.Routing;

Add below code into Global.asax

You are required to add below code into Global.asax page on Application_Error page in your MVC application to get working custom error page.
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;

            case 500:
                action = "InternalServerError";
                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));
}

Error Controller Actions

Here are written controller actions list like Index, NotFound, AccessDenied, InternalServerError etc.
public class ErrorController : Controller
{
    ///     /// Track Common Page Error
    ///     /// 
    [HttpGet]
    public ActionResult Index()
    {
        TempData["error"] = "Error Occurred!";
    return View();
    }
    ///     /// Track Page Not Found Error
    /// 
    /// 
    [HttpGet]
    public ActionResult NotFound()
    {
        TempData["error"] = "Page not Found";
        return View();
    }
    /// 
    /// Track Access Denied
    ///     /// 
    [HttpGet]
    public ActionResult AccessDenied()
    {
        TempData["error"] = "Access Denied";
        return View("Index");
    }

    ///     /// Track Internal Server Error
    ///     /// 
    [HttpGet]
    public ActionResult InternalServerError()
    {
        TempData["error"] = "Internal Server Error";
        return View("Index");
    }
}

Custom Error Razor Views

Below is completely provided code snippet of Razor view engine to display custom error pages to end user. Razor views will remain same to all custom error pages like IndexNotFoundAccessDeniedInternalServerError etc.

@{
    ViewBag.Title = @TempData["error"];
    Layout = null;
}

Error:

@TempData["error"]

Error Description:

@Model.Exception.Message.ToString() @Html.Raw(" ") @Model.ControllerName @Html.Raw(" ") @Model.ActionName

MVC custom error pages

Conclusion

To standardise your ASP.net MVC application, we are all required to customise error pages and show on a particular page with detailed error to make more trustworthy your website in to your online audience. Here, I have lined up all aspects of how to implement custom error pages using MVC application with attached working sample project to setup on your machine to see how it happen in really.

Download Complete Project (visual studio source files)
Download