Global Error Handler For ASP.NET MVC 3

ExceptionExtensions.cs

public static bool IsIt404NotFound(this Exception ex)
{
    var httpException = ex as HttpException;
    return httpException != null && httpException.GetHttpCode() == 404;
}

Global.asax.cs

protected void Application_Error(object sender, EventArgs e)
{
    var exception = Server.GetLastError();

    if (exception.IsIt404NotFound())
    {
        renderNotFoundView();
    }
    else
    {
        renderErrorView(exception);
    }
}

private void renderErrorView(Exception exception)
{
    var exceptionMessageViewData = new[] { new KeyValuePair<string, object>("ExceptionMessage", exception)};
    var currentHtppContextBase = HttpContext.Current.GetHttpContextBase();
    currentHtppContextBase.RenderViewToHttpContextResponse("Error", viewDataPairs: exceptionMessageViewData);
    currentHtppContextBase.SetStatusCodeTo(500);
}

private void renderNotFoundView()
{
    var currentHtppContextBase = HttpContext.Current.GetHttpContextBase();
    currentHtppContextBase.RenderViewToHttpContextResponse("NotFound", "NotFound");
    currentHtppContextBase.SetStatusCodeTo(404);
}

HttpContextBaseExtensions.cs

internal static class HttpContextExtensions
{
    internal static HttpContextBase GetHttpContextBase(this HttpContext httpContext)
    {            return new HttpContextWrapper(httpContext);
    }


    internal static void SetStatusCodeTo(this HttpContextBase httpContextBase, int statusCode)
    {
        httpContextBase.Response.StatusCode = statusCode;
    }

    internal static void RenderViewToHttpContextResponse(this HttpContextBase httpContextBase, string viewName, string forceControllerName = null, IEnumerable<KeyValuePair<string, object>> viewDataPairs = null)
    {
        try
        {
            httpContextBase.Response.Clear();

            var currentRequestContext = ((MvcHandler)httpContextBase.CurrentHandler).RequestContext;
            var factory = ControllerBuilder.Current.GetControllerFactory();
            var controllerName = string.IsNullOrEmpty(forceControllerName)
                                     ? currentRequestContext.RouteData.GetRequiredString("controller")
                                     : forceControllerName;
            var controller = factory.CreateController(currentRequestContext, controllerName);
            var controllerContext = new ControllerContext(currentRequestContext, (ControllerBase)controller);

            var viewResult = new ViewResult { ViewName = viewName };

            if (viewDataPairs != null)
            {
                foreach (var viewData in viewDataPairs)
                {
                    viewResult.ViewData.Add(viewData);
                }
            }

            viewResult.ExecuteResult(controllerContext);
            httpContextBase.Server.ClearError();
        }
        catch
        {
        }
    }
}