Re: [xml] xpath question: parsing or create elements with an expression

[Daniel Veillard <veillard redhat com>]

On Tue, Oct 29, 2002 at 06:06:44PM +0100, Torsten Grundmann wrote:
> Hi,
>
> I have to navigate in a given DOM tree with a xpath expression.
> Searching for data is easy,  but I have also to save data.
>
> The xpath expression look like:
> "/settings/section[ name='configuration']/item[ type='wxDateTime'][ name='datawritten']"
> (I know, xpath can pointed to several items. This isn't the problem in
> my case.)
>
> If a node doesn't exists, it should be create. This contain the

  Well you will have to create it.

> How could I manage this?

  This is completely dependant on the set of constraints on your input document.

> Is there a way to do automatically this with an
> existing function?

  No.

> If not, then as first I have to parse the xpath
> expression. Is there an existing function which can detach the
> hierarchic elements and the attributes?

  An XPath expression is compiled into a tree. You will have to learn
about libxml2 and xpath.c internals. Read tree.h, try to undrstand
how those interfaces are implemented by reading tree.c, then read
xpath.c to see the XPath specific parts. Don't expect to have this done
very easilly, what you're looking for is complex and will require you
to do some significant learning work.

Daniel

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