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What to return from a function if an exception is thrown?

Hi,

I have a function that I call to create an arrayList of objects. I've enclosed it in a 'Try...Catch' block. I return the arrayList at the end of the 'Try' and in the 'Catch' I display a messagebox with whatever the exception is in it's message.

I'm getting a warning that 'Function blah doesn't return a value on all code paths. A null reference exception could occur at run time when the result is used.'

So, I'm just wondering what I'm supposed to do to get rid of this warning? Do I return an empty arrayList and then test for that in the function call? Or is there a better solution?

Thanks,
Chris

Brian Mulder

Hi squeakyloboy,
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a way is to add a finally part to the try catch

Function

Try

Catch ex As Exception

Finally
'this will always run so put the return value here
End Try

end function

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bruintje
share what you know, learn what you don't

squeakyloboy

ASKER

Hi bruintje, thanks for the reply.

Ok, I've moved the return as follows:

Finally

Return tracksList

End Try

...but I get the error 'Branching out of a 'Finally' is not valid'.

Any ideas?

ASKER CERTIFIED SOLUTION

Brian Mulder

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squeakyloboy

ASKER

Ah, got it. That's kinda what I thought but it's good to confirm it.

Thanks a lot!
Chris