Do something on an uncaught exception.

[Bob]

Hi all,

I have a small helper service that is peppered with try-catches for all the
exceptional cases I could think of.
It industriously logs every error it comes across for debugging later on.

Wonderful; however on the odd time it blows a gasket the solution is in
99.9% the same .. restart the service.
Then go away and track down the source of the bug fix-test-deploy.
usually a 5 min fix .. but often a call at 3am ...

Is there a mechanism for catching these "uncaught" exceptions in the
application so that I could then launch another instance of the service and
gracefully close down the 'afflicted' app.

regards Bob

p.s. .. I'm sure explorer.exe does this .. it seems to hang and restart all
the time.

[Michael C]

"Bob" <no*******@nospamSam.com.auwrote in message
news:e9**************@TK2MSFTNGP04.phx.gbl...

Hi all,

I have a small helper service that is peppered with try-catches for all
the exceptional cases I could think of.
It industriously logs every error it comes across for debugging later on.

Wonderful; however on the odd time it blows a gasket the solution is in
99.9% the same .. restart the service.
Then go away and track down the source of the bug fix-test-deploy.
usually a 5 min fix .. but often a call at 3am ...

Is there a mechanism for catching these "uncaught" exceptions in the
application so that I could then launch another instance of the service
and gracefully close down the 'afflicted' app.

Application.ThreadException += new blah....

I'm not sure if you need to do this for each thread you create so it would
be worth testing here. With a service though don't you have a single point
that calls all code so can trap everything there? This is what I have and
don't need to restart the service.

Michael

[AlanT]

>>Is there a mechanism for catching these "uncaught" exceptions in the
application so that I could then launch another instance of the service and
gracefully close down the 'afflicted' app.

>Application.ThreadException += new blah....

If that does not catch everything you might also try the

AppDomain.CurrentDomain.UnhandledException += ....
hth,
Alan.

[ron willoughby]

I am assuming that you are in .net. If so then above the page level which you seem to be catching there are the application level of global.aspx and also the last level below the server of web.config. Both have error traps that you can use. However, there are some errors that are a the server level that never get to the application and those are handled by the server. Look at Application_Error in global.aspx; and customerrors in the web.config.

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http://www.eggheadcafe.com

[Bob]

Thanks for this .. I'll give it a shot ...

regards Bob

[Mike Blake-Knox]

In article <e2**************@TK2MSFTNGP04.phx.gbl>, Michael C wrote:

In a service most code will start from a single point which will probably be*
a timer, so it's easy to catch any exception there.

Except for thread pool threads and asynchronous callback threads. For instance,
an exception thrown in a handler for completion of a socket receive needs to be
handled in a try/catch handler (or by the handler for
AppDomain.CurrentDomain.UnhandledException) as Allan suggested.

Mike

[Michael C]

"Mike Blake-Knox" <mi****@community.nospamwrote in message
news:VA******************@community.nospam...

Except for thread pool threads and asynchronous callback threads. For
instance,
an exception thrown in a handler for completion of a socket receive needs
to be
handled in a try/catch handler (or by the handler for
AppDomain.CurrentDomain.UnhandledException) as Allan suggested.

Excellent suggestion. This could be a problem in my service, I noticed some
exceptions not getting handled when I was developing even though I thought
everything should be caught. I think I probably eliminated them just by
fixing whatever was causing the exception but it would definately be worth
me revisiting it. Thanks for the tip.

Michael