抛出异常并通知用户

Question

I've recently joined an asp.net mvc project well under way where there isnt much consistency in dealing with exceptions in the controller; some devs return data to the client to let the user know whats wrong, others throw them back so they get to the server-level handler that processes and logs them - without letting the user know whats up.

It seems obvious to me that both approaches are wrong on their own, and need to complement each other instead; what I'm stuck at, is how to do that. I assume the eventual exception handler / logger could redirect the user to an error webpage upon catching something particularly nasty, but that limits the mechanism to just severe stuff.

I'm kind of looking for a way to do both "throw" and "return..." at a time when I catch an exception, so I get it sorted and logged server side and get data client side that lets me tell the user there's been a hiccup.

My expertise with asp.net is very limited, and while I believe I understand mvc enough for it to not be an issue, this is kind of a "what is the best practice?" question from someone working with people who dont bother with best practices much.

Answer 1

There is a good project called Elmah for logging errors and exceptions in ASP.NET applications. You can find it here

ELMAH (Error Logging Modules and Handlers) is an application-wide error logging facility that is completely pluggable. It can be dynamically added to a running ASP.NET web application, or even all ASP.NET web applications on a machine, without any need for re-compilation or re-deployment.

Once ELMAH has been dropped into a running web application and configured appropriately, you get the following facilities without changing a single line of your code:

• Logging of nearly all unhandled exceptions.
• A web page to remotely view the entire log of recoded exceptions.
• A web page to remotely view the full details of any one logged exception, including colored stack traces.
• In many cases, you can review the original yellow screen of death that ASP.NET generated for a given exception, even with customErrors mode turned off.
• An e-mail notification of each error at the time it occurs.
• An RSS feed of the last 15 errors from the log.

Answer 2

The MVC application that I am working on implements the Application_Error in the Global.asax to handle exceptions thrown from the application and then redirects the user to a standard error page. The Controller for the error page handles the logging as well as displays just enough information about the error to allow a support person to find their session in the system and help resolve any issues.