C# Discussion Boards - CodeProject

22-May-12 0:01

In a function, I want to catch all exceptions and just log them (they do not really matter), but one specific type of exception must not be handled like this - it must be dealt with in a function farther up the call stack.
Currently, I do something like this:

private void SomeFunction()
{
    try
    {
        //some code which might cause some exceptions
    }
    catch(UserTriedToCheatException)
    {
        throw;
    }
    catch (Exception ex)
    {
        Log(ex.ToString());
    }
}

Though that code works as expected, I am not content with it. That catch-throw looks so terrible.
Do you have "nicer" suggestions?

BobJanova22-May-12 0:08

BobJanova

22-May-12 0:08

Exceptions don't really matter? Hm ...

I don't find your construct too bad but the alternative which expresses your intent (imo) slightly better is:

try {
 // ...
} catch(Exception ex) {
 if(ex is UserTriedToCheatException) throw;
 else Log(ex);
}

Bernhard Hiller22-May-12 2:58

22-May-12 2:58

Looks different, but not so much better that I will change my code. Thanks anyway.

Ravi Bhavnani22-May-12 10:56

Ravi Bhavnani

22-May-12 10:56

OK, but leave out the else - it's extraneous. Smile | :)

/ravi

My new year resolution: 2048 x 1536
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Rob Philpott22-May-12 2:05

Rob Philpott

22-May-12 2:05

If you're just logging the exception, why do you need an exception handler here at all? Just use the one 'further up the callstack'.

Regards,
Rob Philpott.

Bernhard Hiller22-May-12 2:56

22-May-12 2:56

Because of other code to be executed or not. Something like this:

public ReturnType APublicFunction(some params)
{
    try
    {
        //some code here
        SomeType someValue = aPrivateFunction(other params);
        //some more code here
    }
    catch(Exception ex)
    {
        //do something useful with the exceptions which are caught here
    }
}

private SomeType aPrivateFunction(other params)
{
    //some code here
    SomeFunction();
    //some more code here
}

In case of the UserTriedToCheatException, it has to be handled in APublicFunction, and no more other code needs to be executed, while in other cases, the exceptions are not such important, the rest of the functions can still be executed (sufficient fallback functionality provided).

Eddy Vluggen22-May-12 8:59

Eddy Vluggen

22-May-12 8:59

How about something similar to the way TryParse[^] works?

if (SomePrivateFunction(out SomeType SomeParamName))
{
  // insert magic here
}

Bastard Programmer from Hell Suspicious | :suss:

Satish3223-May-12 0:08

Satish32

23-May-12 0:08

you can always invoking a Delegate, which will call the registered private method

Satish

Richard Andrew x6422-May-12 5:19

Richard Andrew x64

22-May-12 5:19

Bernhard Hiller wrote:
That catch-throw looks so terrible.

In my opinion, it won't look so terrible with some good comments around it!

The difficult we do right away...
...the impossible takes slightly longer.

Cracked-Down23-May-12 2:01

Cracked-Down

23-May-12 2:01

Could you please clarify the meaning of up in the hierarchy or the use case where you need such type of exception handling?

I am asking this only because I thing your approach could be wrong?

well even I could be thinking wrong as well Big Grin | :-D

Happy Coding

Bernhard Hiller23-May-12 4:29

23-May-12 4:29

For example: a program starts. Many configuration and option files are read, server connections established etc. Some problems might arise, but fallback mechanisms are provided for many cases. But somewhere down in a function, a manipulation of the license is detected - that must be raised to the topmost level, the user must be told "You bad user $€$€!" and the program shuts down immediately.

Cracked-Down23-May-12 4:49

Cracked-Down

23-May-12 4:49

Ok got it!

Do following things
1. Build two separate hierarchies for exception
1.1 For exception that you want to catch log e.g. LoggableException
1.2 For exception that you want to you caller to handle e.g. NonLoggableExcptions
2. Only catch the LoggableException exceptions - log in your case
3. Don not catch NonLoggableExcptions - these will be automatically traverse to the caller
4. The try block code should only throw these two exceptions or the derived objects from these exceptions
5. Don not catch Exception, its a bad practice, which says anything could be happen in the code. can it be Big Grin | :-D

. this gives bad impression. though I am not sure if any unhanded exception occurs how it is handled in the client server application as I never worked on it

hope this helps to you and solve you problem...
let me know if you need some further help

Happy Coding
Smile | :)

modified 28-May-12 3:00am.

Delegate Conversion to Method? [Solved]

Cracked-Down27-May-12 21:00

Cracked-Down

27-May-12 21:00

did this solution helped you?

blocking USB ports

Pritam Dalvi21-May-12 21:58

Pritam Dalvi

21-May-12 21:58

How to block USB ports in c# application?

Re: blocking USB ports

Richard MacCutchan21-May-12 22:58

Richard MacCutchan

21-May-12 22:58

Use Google[^].

Programming is work, it isn't finger painting. Luc Pattyn

Ravi Sant21-May-12 21:06

Ravi Sant

21-May-12 21:06

Hi,

I have a code to debug, which in delegate block as below.
Since even the F11 steps through it, i think of extracting method out of delegate.
I googled much about this with no ready-help.

private List<IProduct> GetPaginatedProduct(bool IsCalled, IProductPageSortOption paginationOption, IEnumerable<ICustomCriteria> additionalCriteria,string reportStartDate, string reportEndDate)
{

  HibernateDelegate<IList<ProductStaticDataDBBean>> hibDel = delegate(ISession session)
  {
    ....
    //do something with session .. about 300 lines of code...
    ....
  }

}

My question is:
Can I call it like: say delegate(ISession session){ call some function(..) }.
So that I effectively replace inline code with a function call.
Please guide.
Thanks.

Edit: I was not able to break into anonymous code.
Refactoring the delegates to call few methods, containing anonymous code above, made task easier.

// ♫ 99 little bugs in the code,
// 99 bugs in the code
// We fix a bug, compile it again
// 101 little bugs in the code ♫

Tell your manager, while you code: "good, cheap or fast: pick two. "

modified 22-May-12 6:00am.

Keith Barrow21-May-12 21:59

Keith Barrow

21-May-12 21:59

What you have here is an anonymous method, being assigned to a delegate.

I'm surprised that debugging isn't working, you should put a breakpoint inside the delegate to make sure. Stepping in should work. You can refactor quite easily:

HibernateDelegate<IList<ProductStaticDataDBBean>> hibDel = MeaningfulMethodName;
whateverreturntypeyouhave MeaningfulMethodName (ISession session)
  {
    ....
    //do something with session .. about 300 lines of code...
    ....
  }

Let me know if this answers your question, I think I may have the wrong end of the stick Unsure | :~

Sort of a cross between Lawrence of Arabia and Dilbert.[^]
-Or-
A Dead ringer for Kate Winslett[^]

Ravi Sant21-May-12 23:57

Ravi Sant

21-May-12 23:57

I was not able to put a breakpoint inside anonymous code.
Refactoring the delegate to call few methods(and put anonymous code there) solved the problem and debugging.

// ♫ 99 little bugs in the code,
// 99 bugs in the code
// We fix a bug, compile it again
// 101 little bugs in the code ♫

Tell your manager, while you code: "good, cheap or fast: pick two. "

Keith Barrow22-May-12 1:38

Keith Barrow

22-May-12 1:38

Ravi Sant wrote:
I was not able to put a breakpoint inside anonymous code.

Curious: I tried it and it worked (VS2010 Ultimate), I don't remember there being a problem in VS 2008 but that doesn't mean there wasn't.
Sounds like something is Foo'd with VS.

Sort of a cross between Lawrence of Arabia and Dilbert.[^]
-Or-
A Dead ringer for Kate Winslett[^]