Why is InnerException used
in [CSharp]
|
Prev: validate wmf files?
Next: Local service account
From: Tony Johansson on 4 May 2010 06:26 Hi! Some exception has further information in the Inner Exception property. For example the SmtpException has useful information in the InnerException that can be used Here is an example catch (SmtpException ex) { Exception inner = ex.InnerException; MessageBox.Show("Could not send message: " + inner.Message, "Problem sending message", MessageBoxButtons.OK, MessageBoxIcon.Error); } So my question is why is not the InnerException.Message information put into the SmtpException.Message ? //Tony
From: Willem van Rumpt on 4 May 2010 07:16 Tony Johansson wrote: > Hi! > > Some exception has further information in the Inner Exception property. > For example the SmtpException has useful information in the InnerException > that can be used > Here is an example > catch (SmtpException ex) > { > Exception inner = ex.InnerException; > MessageBox.Show("Could not send message: " + inner.Message, > "Problem sending message", MessageBoxButtons.OK, > MessageBoxIcon.Error); > } > > So my question is why is not the InnerException.Message information put into > the SmtpException.Message ? > > //Tony > > What use would it be to copy and repeat the same message in a new exception? The wrapping exception can (potentially) be more clear and provide additional information than the exception thrown from some deep ly nested library call. -- Willem van Rumpt
From: Harlan Messinger on 4 May 2010 07:24 Tony Johansson wrote: > Hi! > > Some exception has further information in the Inner Exception property. > For example the SmtpException has useful information in the InnerException > that can be used > Here is an example > catch (SmtpException ex) > { > Exception inner = ex.InnerException; > MessageBox.Show("Could not send message: " + inner.Message, > "Problem sending message", MessageBoxButtons.OK, > MessageBoxIcon.Error); > } > > So my question is why is not the InnerException.Message information put into > the SmtpException.Message ? An Exception isn't just a message. It has a type, and it has a a HelpLink, a Source, a StackTrace, and a TargetSite. It may even have its own InnerException. All of these may be useful to a calling method or to the user or developer.
From: Göran Andersson on 4 May 2010 07:48 On 2010-05-04 12:26, Tony Johansson wrote: > Hi! > > Some exception has further information in the Inner Exception property. > For example the SmtpException has useful information in the InnerException > that can be used > Here is an example > catch (SmtpException ex) > { > Exception inner = ex.InnerException; > MessageBox.Show("Could not send message: " + inner.Message, > "Problem sending message", MessageBoxButtons.OK, > MessageBoxIcon.Error); > } > > So my question is why is not the InnerException.Message information put into > the SmtpException.Message ? > > //Tony > An exception is usually put as inner exception if it contains information that needs to be retained and can't be combined into a new exception. An exception can contain a lot more than just the message, like a stack trace. A clear example is the SoapException which is thrown when a web service call is answered with a SOAP error message. If the web service is a .NET service, the error message contains a serialised excpetion object from the server. This is deserialised and put in the InnerException of the SoapException object. As the exceptions are created on different servers, they should clearly remain separate instead of trying to be combine them. -- G�ran Andersson _____ http://www.guffa.com
From: Patrice on 4 May 2010 09:19
> So my question is why is not the InnerException.Message information put > into the SmtpException.Message ? Common best practice. It's best to provide separated information that can be gathered easily as needed rather than to pack all in a single item making hard to extract a particular info out of it. Not sure what you want to get in your case, but you could perhaps try ex.ToString()... -- Patrice |