Microsoft XML - Finding the position of a value in a nodelist

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Finding the position of a value in a nodelist

Dave F.

2005-12-29, 10:30 pm

Hi
I'm new to the joys of XML.

I have an XML file:

<?xml version="1.0"?>
<Offset>
<x>0.2</x>
<x>1</x>
<x>2</x>
<x>3</x>
<x>4</x>
<x>4.5</x>
<x>5</x>
<x>7</x>
<x>7.1</x>
</Offset>

Given the value of 4.5, what's the best way to find it's position in the
childnodes?

I know I can get the NodeList:
Set NodeLst = MsDom.selectNodes("/Offset/x/text()")
& iterate it using the item method, but i was wondering if I there was a
quicker/easier way.

I can get the value at position 3 etc. using position(), but is there an
option to do the opposite?

Thanks in advance

Dave F.

Martin Honnen

2005-12-30, 6:37 pm

Dave F. wrote:

> <Offset>
> <x>0.2</x>
> <x>1</x>
> <x>2</x>
> <x>3</x>
> <x>4</x>
> <x>4.5</x>
> <x>5</x>
> <x>7</x>
> <x>7.1</x>
> </Offset>
>
> Given the value of 4.5, what's the best way to find it's position in the
> childnodes?

It depends on what you regard as child nodes, if you are looking for all
element child nodes then you can use the XPath expression
/Offset/x[. = "4.5"][1]/preceding-sibling::*
and for instance do a selectNodes on that, take the length of the
returned node list and add 1 to find the position e.g. with JScript
var position = xmlDocument.selectNodes(
'/Offset/x[. = "4.5"][1]/preceding-sibling::*').length + 1;

If you wanted to consider all kind of child nodes (element, text,
comment etc.) then you need the XPath expression
/Offset/x[. = "4.5"][1]/preceding-sibling::node()
and do the same as above.

--

Martin Honnen --- MVP XML
http://JavaScript.FAQTs.com/

Janwillem Borleffs

2005-12-30, 6:37 pm

Dave F. wrote:
> Given the value of 4.5, what's the best way to find it's position in
> the childnodes?
>
> I know I can get the NodeList:
> Set NodeLst = MsDom.selectNodes("/Offset/x/text()")
> & iterate it using the item method, but i was wondering if I there
> was a quicker/easier way.
>

Try something like:

NodePosition = MsDom.selectNodes("count(x[.='4.5']/preceding-sibling::*) +
1")

JW