How to walk through InnerExceptions?

[Terry Olsen]

How can I walk through the InnerExceptions ? Would the following code be
correct?

Private Sub ShowException(B yVal ex As Exception)
MsgBox(ex.Messa ge)
If ex.InnerExcepti on Is Nothing = False Then _
ShowException(e x.InnerExceptio n)
End Sub

I thought I saw a snippet a while ago using a For...Each loop, but I'm
unable to find it again.

*** Sent via Developersdex http://www.developersdex.com ***

[GhostInAK]

Re: How to walk through InnerExceptions ?

Hello Terry,

I've not had call to walk over inner exceptions, however, if you really want
to, then you'll need to use a recursive function.

Private Function GetInnerExcepti on(byref tException As Exception) As String

Dim tReturn As String = String.Empty

If Not Nothing Is tException Then

tReturn = tException.ToSt ring()

If Not Nothing Is tException.Inne rException Then
tReturn = tReturn & GetInnerExcepti on(tException.I nnerException)
End If

End If

Return tReturn

End Function
[color=blue]
> How can I walk through the InnerExceptions ? Would the following code
> be correct?
>
> Private Sub ShowException(B yVal ex As Exception)
> MsgBox(ex.Messa ge)
> If ex.InnerExcepti on Is Nothing = False Then _
> ShowException(e x.InnerExceptio n)
> End Sub
> I thought I saw a snippet a while ago using a For...Each loop, but I'm
> unable to find it again.
>
> *** Sent via Developersdex http://www.developersdex.com ***
>[/color]

[Göran Andersson]

Re: How to walk through InnerExceptions ?

No, there is no need for a recursive function. It can be done just as
easily using a simple loop:

Private Function GetInnerExcepti on(byref tException As Exception) As String

Dim tReturn As String = String.Empty

Do While Not tException Is Nothing
tReturn &= tException.ToSt ring()
tException = tException.Inne rException
Loop

Return tReturn

End Function


Save the recursion for when it's useful. :)


GhostInAK wrote:[color=blue]
> Hello Terry,
>
> I've not had call to walk over inner exceptions, however, if you really
> want to, then you'll need to use a recursive function.
>
> Private Function GetInnerExcepti on(byref tException As Exception) As String
>
> Dim tReturn As String = String.Empty
>
> If Not Nothing Is tException Then
>
> tReturn = tException.ToSt ring()
>
> If Not Nothing Is tException.Inne rException Then
> tReturn = tReturn & GetInnerExcepti on(tException.I nnerException)
> End If
>
> End If
>
> Return tReturn
>
> End Function
>[color=green]
>> How can I walk through the InnerExceptions ? Would the following code
>> be correct?
>>
>> Private Sub ShowException(B yVal ex As Exception)
>> MsgBox(ex.Messa ge)
>> If ex.InnerExcepti on Is Nothing = False Then _
>> ShowException(e x.InnerExceptio n)
>> End Sub
>> I thought I saw a snippet a while ago using a For...Each loop, but I'm
>> unable to find it again.
>>
>> *** Sent via Developersdex http://www.developersdex.com ***
>>[/color]
>
>[/color]

[Terry Olsen]

Re: How to walk through InnerExceptions ?

Thanks. I knew recursion wasn't necessary because I'd seen it before
done this way.

*** Sent via Developersdex http://www.developersdex.com ***

[GhostInAK]

Re: How to walk through InnerExceptions ?

Hello Göran,

No no no. tException is declared ByRef. You dont wanna be changing it's
value willy-nilly like that. If you want to use a loop like that then pass
the exception ByVal.

-Boo
[color=blue]
> No, there is no need for a recursive function. It can be done just as
> easily using a simple loop:
>
> Private Function GetInnerExcepti on(byref tException As Exception) As
> String
>
> Dim tReturn As String = String.Empty
>
> Do While Not tException Is Nothing
> tReturn &= tException.ToSt ring()
> tException = tException.Inne rException
> Loop
> Return tReturn
>
> End Function
>
> Save the recursion for when it's useful. :)
>
> GhostInAK wrote:
>[color=green]
>> Hello Terry,
>>
>> I've not had call to walk over inner exceptions, however, if you
>> really want to, then you'll need to use a recursive function.
>>
>> Private Function GetInnerExcepti on(byref tException As Exception) As
>> String
>>
>> Dim tReturn As String = String.Empty
>>
>> If Not Nothing Is tException Then
>>
>> tReturn = tException.ToSt ring()
>>
>> If Not Nothing Is tException.Inne rException Then
>> tReturn = tReturn & GetInnerExcepti on(tException.I nnerException)
>> End If
>> End If
>>
>> Return tReturn
>>
>> End Function
>>[color=darkred]
>>> How can I walk through the InnerExceptions ? Would the following code
>>> be correct?
>>>
>>> Private Sub ShowException(B yVal ex As Exception)
>>> MsgBox(ex.Messa ge)
>>> If ex.InnerExcepti on Is Nothing = False Then _
>>> ShowException(e x.InnerExceptio n)
>>> End Sub
>>> I thought I saw a snippet a while ago using a For...Each loop, but
>>> I'm
>>> unable to find it again.
>>> *** Sent via Developersdex http://www.developersdex.com ***
>>>[/color][/color][/color]

[Göran Andersson]

Re: How to walk through InnerExceptions ?

You are right. I didn't notice the byref when I copied the code. There
is no reason to send the reference to the exception by reference. Simply
remove the byref from the method:

Private Function GetInnerExcepti on(tException As Exception) As String

Dim tReturn As String = String.Empty

Do While Not tException Is Nothing
tReturn &= tException.ToSt ring()
tException = tException.Inne rException
Loop

Return tReturn

End Function


GhostInAK wrote:[color=blue]
> Hello Göran,
>
> No no no. tException is declared ByRef. You dont wanna be changing
> it's value willy-nilly like that. If you want to use a loop like that
> then pass the exception ByVal.
>
> -Boo
>[color=green]
>> No, there is no need for a recursive function. It can be done just as
>> easily using a simple loop:
>>
>> Private Function GetInnerExcepti on(byref tException As Exception) As
>> String
>>
>> Dim tReturn As String = String.Empty
>>
>> Do While Not tException Is Nothing
>> tReturn &= tException.ToSt ring()
>> tException = tException.Inne rException
>> Loop
>> Return tReturn
>>
>> End Function
>>
>> Save the recursion for when it's useful. :)
>>
>> GhostInAK wrote:
>>[color=darkred]
>>> Hello Terry,
>>>
>>> I've not had call to walk over inner exceptions, however, if you
>>> really want to, then you'll need to use a recursive function.
>>>
>>> Private Function GetInnerExcepti on(byref tException As Exception) As
>>> String
>>>
>>> Dim tReturn As String = String.Empty
>>>
>>> If Not Nothing Is tException Then
>>>
>>> tReturn = tException.ToSt ring()
>>>
>>> If Not Nothing Is tException.Inne rException Then
>>> tReturn = tReturn & GetInnerExcepti on(tException.I nnerException)
>>> End If
>>> End If
>>>
>>> Return tReturn
>>>
>>> End Function
>>>
>>>> How can I walk through the InnerExceptions ? Would the following code
>>>> be correct?
>>>>
>>>> Private Sub ShowException(B yVal ex As Exception)
>>>> MsgBox(ex.Messa ge)
>>>> If ex.InnerExcepti on Is Nothing = False Then _
>>>> ShowException(e x.InnerExceptio n)
>>>> End Sub
>>>> I thought I saw a snippet a while ago using a For...Each loop, but
>>>> I'm
>>>> unable to find it again.
>>>> *** Sent via Developersdex http://www.developersdex.com ***
>>>>[/color][/color]
>
>[/color]