"Martin Honnen" <mahotrash@yahoo.de> wrote in message
news:OnnIhB6AFHA.2880@TK2MSFTNGP14.phx.gbl...
>
>
> Larry Woods wrote:
>
> > How do I test for the existence of a nodal attribute?
> >
> > The following snippet terminates with an error "Object reference not
set to
> > an instance of an object."
> >
> > Snippet:
> >
> > For Each oChild In oNode.ChildNodes
> > If Not (oChild.Attributes.ItemOf("key") Is Nothing) Then
> > ..............................
> > End of Snippet
> >
> > Testing in Intermediate mode:
> >
> > ? ochild.Attributes.ItemOf("key")
> > Referenced object has a value of 'Nothing'.
> >
> > So, why doesn't the "Is Nothing" test work?
>
> It could be that the For Each loop finds a child node which is not an
> element node and therefore doesn't have attributes at all, in that case
> oChild.Attributes is null in C# (which I think is Nothing in VB.NET) and
> then the attempt to access .ItemOf on null (respectively Nothing) causes
> the error.
> So you need to make sure you have an element node by checking NodeType
> for instance before you try to access Attributes.
>
> --
>
> Martin Honnen
> http://JavaScript.FAQTs.com/

Larry Woods wrote:

> How do I test for the existence of a nodal attribute?
>
> The following snippet terminates with an error "Object reference not set to
> an instance of an object."
>
> Snippet:
>
> For Each oChild In oNode.ChildNodes
> If Not (oChild.Attributes.ItemOf("key") Is Nothing) Then
> ..............................
> End of Snippet
>
> Testing in Intermediate mode:
>
> ? ochild.Attributes.ItemOf("key")
> Referenced object has a value of 'Nothing'.
>
> So, why doesn't the "Is Nothing" test work?