XmlNode.SelectNodes, order of nodes

[Vikram Vamshi]

If I execute XmlNode.SelectN odes("some xpath query") and then use foreach to
iterate over it.
Will it guaratee that the order of nodes I get will be same as the order of
nodes in the original xml document?

Can someone point me to a document which states that the order is (or is
not) guarateened (I could not find any when i did my search on msdn).

This is very crucial to our design, otherwise I will have to add a
"sequence" attribute and then order by the sequence.

Thanks in advance.
--
Vikram Vamshi
Database Engineer
Eclipsys Corporation

[Martin Honnen]

Re: XmlNode.SelectN odes, order of nodes



Vikram Vamshi wrote:[color=blue]
> If I execute XmlNode.SelectN odes("some xpath query") and then use foreach to
> iterate over it.
> Will it guaratee that the order of nodes I get will be same as the order of
> nodes in the original xml document?[/color]

I think XPath rules will apply so on e.g. the child axis the nodes will
be in document order, on e.g. the preceding-sibling axis the nodes will
be in reversed document order.

See the XPath specification <http://www.w3.org/TR/xpath#axes>, an
excerpt says:
"An axis is either a forward axis or a reverse axis. An axis that
only ever contains the context node or nodes that are after the context
node in document order is a forward axis. An axis that only ever
contains the context node or nodes that are before the context node in
document order is a reverse axis. Thus, the ancestor, ancestor-or-self,
preceding, and preceding-sibling axes are reverse axes; all other axes
are forward axes. Since the self axis always contains at most one node,
it makes no difference whether it is a forward or reverse axis."


--

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

[Vikram Vamshi]

Re: XmlNode.SelectN odes, order of nodes

Martin,
I did read the document, from what I understand it says that the nodes in
the node-set are based upon the axis that you select.
Howerver it does not impose any ordering on the nodes within the final
node-set.
So the 'axis' simply acts like a filtering mechanism. Did I misinterpret it?

Thanks for taking your time to respond.

Vikram
--
Vikram Vamshi
Database Engineer
Eclipsys Corporation
"Martin Honnen" <mahotrash@yaho o.de> wrote in message
news:%237RNIQkj GHA.1272@TK2MSF TNGP03.phx.gbl. ..[color=blue]
>
>
> Vikram Vamshi wrote:[color=green]
>> If I execute XmlNode.SelectN odes("some xpath query") and then use foreach
>> to iterate over it.
>> Will it guaratee that the order of nodes I get will be same as the order
>> of nodes in the original xml document?[/color]
>
> I think XPath rules will apply so on e.g. the child axis the nodes will be
> in document order, on e.g. the preceding-sibling axis the nodes will be in
> reversed document order.
>
> See the XPath specification <http://www.w3.org/TR/xpath#axes>, an excerpt
> says:
> "An axis is either a forward axis or a reverse axis. An axis that only
> ever contains the context node or nodes that are after the context node in
> document order is a forward axis. An axis that only ever contains the
> context node or nodes that are before the context node in document order
> is a reverse axis. Thus, the ancestor, ancestor-or-self, preceding, and
> preceding-sibling axes are reverse axes; all other axes are forward axes.
> Since the self axis always contains at most one node, it makes no
> difference whether it is a forward or reverse axis."
>
>
> --
>
> Martin Honnen --- MVP XML
> http://JavaScript.FAQTs.com/[/color]

[Oleg Tkachenko [MVP]]

Re: XmlNode.SelectN odes, order of nodes

Vikram Vamshi wrote:[color=blue]
> If I execute XmlNode.SelectN odes("some xpath query") and then use foreach to
> iterate over it.
> Will it guaratee that the order of nodes I get will be same as the order of
> nodes in the original xml document?
>
> Can someone point me to a document which states that the order is (or is
> not) guarateened (I could not find any when i did my search on msdn).
>
> This is very crucial to our design, otherwise I will have to add a
> "sequence" attribute and then order by the sequence.[/color]

http://msdn2.microsoft.com/en-us/mic...lectnodes.aspx

"Returns a XMLNodes collection that represents all the nodes that match
a specified XPath string in the order in which they appear."


--
Oleg Tkachenko [XML MVP, MCAD]
http://www.XmlLab.Net | http://www.XLinq.Net | http://blog.tkachenko.com

[Vikram Vamshi]

Re: XmlNode.SelectN odes, order of nodes

That is from the word interop documentation, do you think the same will hold
true for the .net 2.0 framework.

--
Vikram Vamshi
Database Engineer
Eclipsys Corporation
"Oleg Tkachenko [MVP]" <some@body.co m> wrote in message
news:448E85BC.2 020608@body.com ...[color=blue]
> Vikram Vamshi wrote:[color=green]
>> If I execute XmlNode.SelectN odes("some xpath query") and then use foreach
>> to iterate over it.
>> Will it guaratee that the order of nodes I get will be same as the order
>> of nodes in the original xml document?
>>
>> Can someone point me to a document which states that the order is (or is
>> not) guarateened (I could not find any when i did my search on msdn).
>>
>> This is very crucial to our design, otherwise I will have to add a
>> "sequence" attribute and then order by the sequence.[/color]
>
> http://msdn2.microsoft.com/en-us/mic...lectnodes.aspx
>
> "Returns a XMLNodes collection that represents all the nodes that match a
> specified XPath string in the order in which they appear."
>
>
> --
> Oleg Tkachenko [XML MVP, MCAD]
> http://www.XmlLab.Net | http://www.XLinq.Net | http://blog.tkachenko.com[/color]

[Oleg Tkachenko [MVP]]

Re: XmlNode.SelectN odes, order of nodes

Vikram Vamshi wrote:[color=blue]
> That is from the word interop documentation, do you think the same will hold
> true for the .net 2.0 framework.[/color]

Yes. But if your whole design depends on this feature you better sort
selected nodes explicitly. XmlNode.SelectN odes is just a wrapper for
XPathNavigator. Select, so instead SelectNodes use XPathNavigator,
compiled XPathExpression and AddSort() method to sort nodes by preceding
nodes count.

--
Oleg Tkachenko [XML MVP, MCAD]
http://www.XmlLab.Net | http://www.XLinq.Net | http://blog.tkachenko.com

[Vikram Vamshi]

Re: XmlNode.SelectN odes, order of nodes

Thanks!!!

--
Vikram Vamshi
Database Engineer
Eclipsys Corporation
"Oleg Tkachenko [MVP]" <some@body.co m> wrote in message
news:448FD306.8 030209@body.com ...[color=blue]
> Vikram Vamshi wrote:[color=green]
>> That is from the word interop documentation, do you think the same will
>> hold true for the .net 2.0 framework.[/color]
>
> Yes. But if your whole design depends on this feature you better sort
> selected nodes explicitly. XmlNode.SelectN odes is just a wrapper for
> XPathNavigator. Select, so instead SelectNodes use XPathNavigator, compiled
> XPathExpression and AddSort() method to sort nodes by preceding nodes
> count.
>
> --
> Oleg Tkachenko [XML MVP, MCAD]
> http://www.XmlLab.Net | http://www.XLinq.Net | http://blog.tkachenko.com[/color]

[Nagendra Kumar]

Re: XmlNode.SelectN odes, order of nodes


Hi, Nice Replies those are worth ful..

Please have a look at my blog

http://dotnethangout.blogspot.com/2007/02/xml-in-net.html

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

[Nagendra Kumar]

Re: XmlNode.SelectN odes, order of nodes



Please Visit

http://dotnethangout.blogspot.com/2007/02/xml-in-net.html

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