Question

I have custom error handling defined for my application and it all works wonderfully – when a resource cannot be found, the correct ‘NotFound’ view renders. When an unhanlded exception occurs, the ‘ServerError’ view renders.

The problem I am facing is that my application insists on trying to find a View called ‘Error’ but doesn’t find it, as i don’t have one and thus this exception gets thrown during my custom error handling routine:

“The view ‘Error’ or its master was not found or no view engine supports the searched locations. The following locations were searched: … “

I have an Application_Error event handler which does the logging of all unhandled exceptions:

protected void Application_Error(Object sender, EventArgs e)
{
    Exception lastEx = Server.GetLastError();

    // Attempt to Log the error
    try
    {
        Utils.Logger.Error(lastEx);
    }
    catch (Exception loggingEx)
    {
        // Try and write the original ex to the Trace
        Utils.TryTrace(lastEx.Message);

        // Try and write the logging exception to the Trace
        Utils.TryTrace(loggingEx.Message);
    }
}

I have customErrors turned ‘On’ in my web.config:

<customErrors mode="On" defaultRedirect="blah">
    <error statusCode="404" redirect="dee"/>
    <error statusCode="500" redirect="blah"/>
</customErrors>

And i have routes defined in my Global.asax.cs RegisterRoutes method which correspond to the Redirect defined in web.config above:

routes.MapRoute(
    "Error - 404",
    "dee",
    new { controller = "Error", action = "NotFound" }
    );

routes.MapRoute(
    "ServerError", // When this route is matched we want minimal error info displayed
    "blah",
    new { controller = "Error", action = "ServerError" }
    );

I have a BaseController which contains an OnActionExecuted routine:

protected override void OnActionExecuted(ActionExecutedContext filterContext)
{
    Logger.Info(String.Format(Constants.LOG_ACTION_EXECUTED, filterContext.Controller.ToString(), filterContext.ActionDescriptor.ActionName));
    // Log any exceptions
    if (filterContext.Exception != null)
    {
        Stack<string> messages = new Stack<string>();
        Exception current = filterContext.Exception;
        messages.Push(current.Message);
        while (current.InnerException != null)
        {
            messages.Push(current.InnerException.Message);                    
            current = current.InnerException;
        }
        StringBuilder result = new StringBuilder();
        while (messages.Count != 0)
        {
            result.Append(messages.Pop());
            string nextline = messages.Count > 0 ? "OUTER EXCEPTION " + messages.Count + ": " : "";
            result.Append(Environment.NewLine);
        }
        Logger.Error(result.ToString());
    }
    base.OnActionExecuted(filterContext);
}

Is there somewhere else that the Framework defines which view to render in the event of an unhandled exception?

Is my custom error handling routine missing a final step which would ensure that the Framework no longer expects to find the ‘Error’ view???

Answer 1

I had already removed the line which added the filter automatically to all Controllers…as suggested by Eranga – so that wasn’t what was causing the Framework to search for the ‘Error’ view.

The problem i was experiencing was being caused by some left over [HandleError] attribute tags sitting on top of one of my Controllers.

So it is interesting to note that: despite the fact that my controller had the [HandleError] attribute decorated at the top of its class definition, my custom error handling routine, as defined in the web.config, was still being called – and was correctly rendering the required Views…

The framework error handling (as defined by the HandleErrorAttribute) would fail, my Application_Error would catch the Exception and silently log it to the Database via my ‘Logger’ instance…then my custom error handling routine would complete successfully.