RE: [xsl] Using position predicate in XPath string within selectSingleNode DOM method

Subject: RE: [xsl] Using position predicate in XPath string within selectSingleNode DOM method
From: "Matthieu Ricaud" <matthieu.ricaud@xxxxxxx>
Date: Thu, 25 Nov 2004 10:54:16 +0100
Hi Pieter,

Thanks a lot for your proposition of finding a solution together to my
problem.

At the moment I was going to tell you what ITEM[1] return, I noticed it
returns the SECOND <ITEM> node and not the FIRST !

And actually this is the solution of my problem !

With SelectSingleNode Method the Xpath position indice starts at 0 and not 1
like in XSL's Xpath query.

That means for example  :

SelectSingleNode("/FORMATION[0]/EPREUVES[0]/EPREUVEAOPT[1]/OPTION[0]")

select the same node as :

<xsl:for-each select="/FORMATION[1]/EPREUVES[1]/EPREUVEAOPT[2]/OPTION[1]">

Everything's ok now ! exept that I'm really angry with Microsoft which did
not specify this in the msdn !

But anyway, that's great !!

thanks all for helping !

Matt


-----Message d'origine-----
De : Pieter Reint Siegers Kort [mailto:pieter.siegers@xxxxxxxxxxx]
Envoyi : jeudi 25 novembre 2004 00:17
@ : xsl-list@xxxxxxxxxxxxxxxxxxxxxx
Objet : RE: [xsl] Using position predicate in XPath string within
selectSingleNode DOM method


Hi Matthieu,

I put you on the wrong track. Like David told you, selecting the third
element should be foo[3], not foo[.=3]. I guess I was too quick in
suggesting it.

So first, you need to change the line
	Set objNode=objXML.documentElement.SelectSingleNode("ITEM[.=2]")
back into
	Set objNode=objXML.documentElement.SelectSingleNode("ITEM[2]")

This should get you the second node element- when it works like it should.
:-)

Now, let's go to the root of the problem. The Xpath is correct.
But I wanna know something from you. You wrote:

> Curisously I get it work when writing ITEM[1] (but not for ITEM[.=1]) When
writing ITEM[2] or ITEM[.=2] it doesn't work anymore !

Exactly what node element does ITEM[1] return? Just curiousity, but it may
make a point here.

Just to clarify, I never have used a DOM like this, I always write a
stylesheet and apply it on the source XML as an XSLT. That being said, it's
clear that (still) I do not have any clue why it doesn't work, but maybe we
can find out together.

Cheers,
<prs/>


-----Original Message-----
From: Matthieu Ricaud [mailto:matthieu.ricaud@xxxxxxx]
Sent: Wednesday, November 24, 2004 8:16 AM
To: xsl-list@xxxxxxxxxxxxxxxxxxxxxx
Subject: RE: [xsl] Using position predicate in XPath string within
selectSingleNode DOM method

Thanks all for your answer and interess !

David I totally agree with

" ITEM[1] selects the first ITEM
ITEM[.=1] selects all ITEMs with string value numerically equal to 1."

It's just that I tried Pieter's suggestion ...unsuccessfully.

Emmanouil

"In sarissa i implement the selectSingleNode by appending '[1]' to the xpath
expression then calling selectNodes. Maybe MSXML's implementation has the
same flaw ;-)"

I actually append '[1]' (or generaly '[n]' n>0) to my Xpath before apply the
SelectSingleNode method and this precisely this '[n]' which make my parser
not matching anynode !

My Xpath expression work perfectly if I put it within a <xsl:value-of> in an
XSL file applied to my XML but when I put it in  SelectSingleNode () within
an asp page (see my last mail) it do not work...

So it's not an Xpath problem, the question is why a correct Xpath expression
don't work with SelectSingleNode () ?
Is it a bug, an exeption ?

The MSDN spec about SelectSingleNode say :
"var objXMLDOMNode = oXMLDOMNode.selectSingleNode(queryString);
Where queryString is a string specifying an XPath expression."

Isn't "ITEM[2]" a correct XPath expression ?!
(PS : I'm sure my oXMLDOMNode as 2 ITEM childrens)

This question is more about DOM method implementation, so maybe it shouldn't
be posted hier ?
sorry if so.
But anyway if someone have a solution, I'll be gratefull to him ;)

Matt

-----Message d'origine-----
De : Emmanouil Batsis [mailto:Emmanouil.Batsis@xxxxxxxxxxx]
Envoye : mercredi 24 novembre 2004 13:04 A : xsl-list@xxxxxxxxxxxxxxxxxxxxxx
Objet : Re: [xsl] Using position predicate in XPath string within
selectSingleNode DOM method


David Carlisle wrote:

>do you wrap the expression in () before appending [1] (you need to)
>
>(/a/b/c)[1]
>
>will select at most 1 node
>
>/a/b/c[1]
>
>will select all c nodes that are the first child of a b.
>
>
Now that you mention it...

Cheers,

Manos

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