Question

Which is the best way to handle a system error in ASP.NET MVC? I’ve watched a video on DimeCast.net in which the guy used the global.ascx file to write a method Application_Error to handle the errors. But currently, I’m handling my errors inside the web.config file.

Could someone point me in the right direction on how to properly handle errors? This could be:

1. syntax error
2. exceptions
3. 404 and other page/file not found errors

The application is fairly large.

Answer 1

Very likely you are going to need a combination of approaches. Some errors can be handled directly in your models, others in your controllers, and some others might need to be handled all the way to the application level (either via web.config or via the global.ascx.)

I prefer to handle the errors in the global.ascx rather than via redirection in web.config because in the global.ascx I have more information about the request that caused the error where as if I do a redirect via the web.config settings some of that information is lost by the time my error page receives the request.

A few weeks ago I just noticed that 404 errors are better not handled via the web.config because that (by design) causes an HTTP redirect code 302 rather than a true HTTP 404 code that indicates the client that the resource does not exist. I have a post on my blog where I cover this in detail http://hectorcorrea.com/Blog/Returning-HTTP-404-in-ASP.NET-MVC

Using ELMAH as Brook suggested is also a very good idea.