Multiple Catch blocks that do the same thing...

[User 11360346]

Yes it has purpose. You should see this msdn article. [^] But it wasn't utilized as suppose to.

[OriginalGriff]

There is a recommended practice where you catch the minimum exception you can: SocketException instead of Exception for example, but that code's silly. It's possible that he planned to come back and do something different for the SocketException later and never got round to it, but if that's the case the author still needs a thump upside the head... :laugh:

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[OriginalGriff]

I looked, I saw: but I didn't see a purpose to having two exception catchers that do the same thing. Yes, if the SocketException catcher logged it differently, or re-tried or similar, and the Exception catcher did a generic log-and-exit instead then it's would have a purpose. But two exceptions (one of which catches everything) that do the same thing? I see no point, except to duplicate code and potentially cause a maintenance problem if the logging mechanism changes.

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[User 11360346]

We can't predict looking the above code since we don't know what Dosomething() method exactly do. What we can infer is that there is a socket processing behind since there is a catch exception on it.

[Mike Hankey]

The only thing I can think of is that he didn't know that both were the same and just wanted to keep a separation of concern?

New version: WinHeist Version 2.1.1 new web site. I know the voices in my head are not real but damn they come up with some good ideas!

[Sascha Lefevre]

It's irrelevant what DoSomething() does in regard to the catch-blocks. In case of an exception, either the first or the second catch block gets executed and they do exactly the same, so the more specific one is superfluous.

If the brain were so simple we could understand it, we would be so simple we couldn't. — Lyall Watson

[User 11360346]

They don't occur exactly with the same reason. Off course both catches exception but how each one will occur determine by the actual method logic. Suppose Dosomething() has DB process, then where you will think possible to be catched if error happens. On catch (Exception ex) block and where do you think the socket error will be catched on (SocketException sex). That is why the method logic determine the exception occurence.

[Jacquers]

Typically you would want to handle a socket exception different than a general exception. Maybe an oversight in this case that both are handled the same way. Might have been put in there for debugging.

[OriginalGriff]

It doesn't matter. Regardless of what exception is thrown, the code executed will be identical. Which means that the separate catch for the "lesser" exception need not be there at all. And if it needed be there, why put it in? All that does is leave a "hole" where duplicated code can become different over time and cause other problems - that's one of the advantages of inheritance: it removes the need to "copy and paste" code by reusing a single method in all derived classes. So if the method needs to be changed, it's in one single place instead of scattered all over the file and prone to being missed when the updates are done.

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[Sascha Lefevre]

I assume we're talking past each other. The question isn't if catch blocks catching different types of exceptions can be useful but if it's of any use in this concrete case - which it isn't because the exceptions aren't handled differently.

If the brain were so simple we could understand it, we would be so simple we couldn't. — Lyall Watson

[User 11360346]

We all know that managed .Net exception are derived from Exception class. If you are asking why the rest of derived Exception such as socketexception, Dbexception are created then that is another question. And it won't be necessary to allow multiple catch statement block from the compiler. Off course if you leave/comment out the above socketexception then the error definitely go to exception block, b/c of the reason that I stated above. Onething sure to know here, you can't determine to refactor the code by looking that code only, even we don't know either a SocketException will occur or not. G. Day

[CPallini]

Well, that could have been more interesting, e.g.

catch (SocketException e)
{
Console.WriteLine(e.Message);
conn.connecting = false;
throw;
}
catch (Exception e)
{
Console.WriteLine(e.Message);
conn.connecting = false;
}

:omg:

[ZurdoDev]

OriginalGriff wrote:

It's possible that he planned to come back and do something different for the SocketException later and never got round to it

That was my thought exactly. :thumbsup:

There are only 10 types of people in the world, those who understand binary and those who don't.

[OriginalGriff]

It doesn't matter if a SocketException or an AliensLandedOnWhiteHouseLawnException occurs with that code: the code that is executed is identical regardless. That is the point. Not that Socket Exceptions are derived from Exception - we all know that - but that having a separate catch block is silly if the code executed is the same anyway! Look at the code. Assume a SocketException occurs in the method. What lines of code are executed? Now assume that a AliensLandedOnWhiteHouseLawnException occurs instead. What lines of code are executed? :laugh:

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[User 11360346]

It does matter, a self ref [^] How do you know the code executed the same ? YOU DON'T KNOW WHAT THE METHOD(Dosomething()) DO. What we know both exception was not utilized as such.

[OriginalGriff]

Member 11394652 wrote:

YOU DON'T KNOW WHAT THE METHOD(Dosomething()) DO

Seriously, it doesn't matter. Look at the code we do have:

catch (SocketException e)
{
Console.WriteLine(e.Message);
conn.connecting = false;
}
catch (Exception e)
{
Console.WriteLine(e.Message);
conn.connecting = false;
}

The code in each catch block is identical. :laugh:

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[PIEBALDconsult]

Just useful while debugging; you can have a breakpoint in one block but not the other; but it should be removed afterward.

[User 11360346]

Are you saying the message will always be the same ? This is a trick, If you do get it. :)

[Vikram A Punathambekar]

Member 11394652 wrote:

SocketException sex

:)

Cheers, विक्रम "We have already been through this, I am not going to repeat myself." - fat_boy, in a global warming thread :doh:

[OriginalGriff]

Yes. The message comes from the Exception object, and will the same regardless of which catch block catches it: for a SocketException it will print a socket based message, for an AliensLandedOnWhiteHouseLawnException, it will print a message in Klingon. But it is irrelevant which catch block prints it, because they both use the same code to do that. There is only any point in having separate catches if they do different things:

catch (SocketException e)
{
Console.WriteLine("Problem with socket: {0}", e.Message);
conn.connecting = false;
}
catch (Exception e)
{
Console.WriteLine("An unknown error occured: {0}", e.Message);
conn.connecting = false;
}

Or even:

catch (SocketException e)
{
Console.WriteLine("It's life Jim: {0}", e.Message);
conn.connecting = false;
}
catch (AliensLandedOnWhiteHouseLawnException e)
{
Console.WriteLine("Klingons on the starboard bow, starboard bow, starboard bow\nKlingons on the starboard bow, starboard bow Jim!: {0}", e.Message);
conn.connecting = false;
}
catch (Exception e)
{
Console.WriteLine("But not as we know it: {0}", e.Message);
conn.connecting = false;
}

See what we mean?

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