XPath help needed

[Joe]

Hello All:

I have an xml document with the following structure, where Form is the
document element:

<Form>
<Content>
<Line>blah blah blah</Line>
<Line>
<PresentationGroup>
miscellaneous tags
</PresentationGroup>
</Line>
<Line>blah blah blah 2</Line>
<Line>
<PresentationGroup>
miscellaneous tags
</PresentationGroup>
</Line>
</Content>
</Form>

I want an XPath to the last PresentationGroup node (there are multiple
PresentationGroup nodes per xml document and the number of PresentationGroup
nodes per document changes from one document to the next). I've tried
"Content/Line/PresentationGroup[last()]" and am getting nothing.

My code looks like:

xmlDoc.DocumentElement.SelectSingleNode("Content/Line/PresentationGroup[last()]")

This returns Nothing. I can't figure out why, although I'm sure that it's
simple!

Can anyone see what I am doing wrong?

TIA,
--
Joe

[Phillip Williams]

xmlDoc.DocumentElement.SelectSingleNode("//PresentationGroup[last()]")
or
xmlDoc.DocumentElement.SelectSingleNode("/Form/Content/Line/PresentationGroup[last()]")
--
HTH,
Phillip Williams
http://www.societopia.net
http://www.webswapp.com
"Joe" wrote:

Hello All:

I have an xml document with the following structure, where Form is the
document element:

<Form>
<Content>
<Line>blah blah blah</Line>
<Line>
<PresentationGroup>
miscellaneous tags
</PresentationGroup>
</Line>
<Line>blah blah blah 2</Line>
<Line>
<PresentationGroup>
miscellaneous tags
</PresentationGroup>
</Line>
</Content>
</Form>

I want an XPath to the last PresentationGroup node (there are multiple
PresentationGroup nodes per xml document and the number of PresentationGroup
nodes per document changes from one document to the next). I've tried
"Content/Line/PresentationGroup[last()]" and am getting nothing.

My code looks like:

xmlDoc.DocumentElement.SelectSingleNode("Content/Line/PresentationGroup[last()]")

This returns Nothing. I can't figure out why, although I'm sure that it's
simple!

Can anyone see what I am doing wrong?

TIA,
--
Joe

[Joe]

Phillip,

I have tried both of these. For some reason each returns the first
PresentationGroup. Any idea why?

--
Joe
"Phillip Williams" wrote:

xmlDoc.DocumentElement.SelectSingleNode("//PresentationGroup[last()]")
or
xmlDoc.DocumentElement.SelectSingleNode("/Form/Content/Line/PresentationGroup[last()]")
--
HTH,
Phillip Williams
http://www.societopia.net
http://www.webswapp.com
"Joe" wrote:

Hello All:

I have an xml document with the following structure, where Form is the
document element:

<Form>
<Content>
<Line>blah blah blah</Line>
<Line>
<PresentationGroup>
miscellaneous tags
</PresentationGroup>
</Line>
<Line>blah blah blah 2</Line>
<Line>
<PresentationGroup>
miscellaneous tags
</PresentationGroup>
</Line>
</Content>
</Form>

I want an XPath to the last PresentationGroup node (there are multiple
PresentationGroup nodes per xml document and the number of PresentationGroup
nodes per document changes from one document to the next). I've tried
"Content/Line/PresentationGroup[last()]" and am getting nothing.

My code looks like:

xmlDoc.DocumentElement.SelectSingleNode("Content/Line/PresentationGroup[last()]")

This returns Nothing. I can't figure out why, although I'm sure that it's
simple!

Can anyone see what I am doing wrong?

TIA,
--
Joe

[Martin Honnen]

Joe wrote:

I have an xml document with the following structure, where Form is the
document element:

<Form>
<Content>
<Line>blah blah blah</Line>
<Line>
<PresentationGroup>
miscellaneous tags
</PresentationGroup>
</Line>
<Line>blah blah blah 2</Line>
<Line>
<PresentationGroup>
miscellaneous tags
</PresentationGroup>
</Line>
</Content>
</Form> xmlDoc.DocumentElement.SelectSingleNode("Content/Line/PresentationGroup[last()]")

Here is a complete C# code snippet with your provided XML as the input
XML and your provided XPath expression, that of course finds the element:

string xmlMarkup = @"<Form>
<Content>
<Line>blah blah blah</Line>
<Line>
<PresentationGroup>
miscellaneous tags
</PresentationGroup>
</Line>
<Line>blah blah blah 2</Line>
<Line>
<PresentationGroup>
miscellaneous tags
</PresentationGroup>
</Line>
</Content>
</Form>";
XmlDocument xmlDocument = new XmlDocument();
xmlDocument.LoadXml(xmlMarkup);
XmlElement presentationGroup =
xmlDocument.DocumentElement.SelectSingleNode(@"Con tent/Line/PresentationGroup[last()]")
as XmlElement;
if (presentationGroup != null) {
Console.WriteLine(presentationGroup.OuterXml);
}
else {
Console.WriteLine("No element found.");
}

So somewhere your real code and/or real XML is more complex. Just
guessing, does that XML document declare namespaces, in particular a
default namespace e.g.
<Form xmlns="http://example.com/2006/ns1">
? Then check
<http://www.faqts.com/knowledge_base/view.phtml/aid/34022/fid/616>

--

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

[Joe]

Martin,

In all honesty, I do not declare a namespace. Should I?
--
Joe
"Martin Honnen" wrote:

Joe wrote:

I have an xml document with the following structure, where Form is the
document element:

<Form>
<Content>
<Line>blah blah blah</Line>
<Line>
<PresentationGroup>
miscellaneous tags
</PresentationGroup>
</Line>
<Line>blah blah blah 2</Line>
<Line>
<PresentationGroup>
miscellaneous tags
</PresentationGroup>
</Line>
</Content>
</Form>

xmlDoc.DocumentElement.SelectSingleNode("Content/Line/PresentationGroup[last()]")

Here is a complete C# code snippet with your provided XML as the input
XML and your provided XPath expression, that of course finds the element:

string xmlMarkup = @"<Form>
<Content>
<Line>blah blah blah</Line>
<Line>
<PresentationGroup>
miscellaneous tags
</PresentationGroup>
</Line>
<Line>blah blah blah 2</Line>
<Line>
<PresentationGroup>
miscellaneous tags
</PresentationGroup>
</Line>
</Content>
</Form>";
XmlDocument xmlDocument = new XmlDocument();
xmlDocument.LoadXml(xmlMarkup);
XmlElement presentationGroup =
xmlDocument.DocumentElement.SelectSingleNode(@"Con tent/Line/PresentationGroup[last()]")
as XmlElement;
if (presentationGroup != null) {
Console.WriteLine(presentationGroup.OuterXml);
}
else {
Console.WriteLine("No element found.");
}

So somewhere your real code and/or real XML is more complex. Just
guessing, does that XML document declare namespaces, in particular a
default namespace e.g.
<Form xmlns="http://example.com/2006/ns1">
? Then check
<http://www.faqts.com/knowledge_base/view.phtml/aid/34022/fid/616>

--

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

[Phillip Williams]

Oh my mistake, you should be looking for the last line's presentation group
element like this:
xmlDoc.DocumentElement.SelectSingleNode("//Line[last()]/PresentationGroup")
or
xmlDoc.DocumentElement.SelectSingleNode("/Form/Content/Line[last()]/PresentationGroup[last()]")
--
HTH,
Phillip Williams
http://www.societopia.net
http://www.webswapp.com
"Joe" wrote:

Phillip,

I have tried both of these. For some reason each returns the first
PresentationGroup. Any idea why?

--
Joe
"Phillip Williams" wrote:

xmlDoc.DocumentElement.SelectSingleNode("//PresentationGroup[last()]")
or
xmlDoc.DocumentElement.SelectSingleNode("/Form/Content/Line/PresentationGroup[last()]")
--
HTH,
Phillip Williams
http://www.societopia.net
http://www.webswapp.com
"Joe" wrote:

Hello All:

I have an xml document with the following structure, where Form is the
document element:

<Form>
<Content>
<Line>blah blah blah</Line>
<Line>
<PresentationGroup>
miscellaneous tags
</PresentationGroup>
</Line>
<Line>blah blah blah 2</Line>
<Line>
<PresentationGroup>
miscellaneous tags
</PresentationGroup>
</Line>
</Content>
</Form>

I want an XPath to the last PresentationGroup node (there are multiple
PresentationGroup nodes per xml document and the number of PresentationGroup
nodes per document changes from one document to the next). I've tried
"Content/Line/PresentationGroup[last()]" and am getting nothing.

My code looks like:

xmlDoc.DocumentElement.SelectSingleNode("Content/Line/PresentationGroup[last()]")

This returns Nothing. I can't figure out why, although I'm sure that it's
simple!

Can anyone see what I am doing wrong?

TIA,
--
Joe

[Joe]

I'm not looking for the last line's presentation group; I'm looking for the
last presentation group. I do know that the last one will be in a Line node,
but it will not be in the last Line node.

--
Joe
"Phillip Williams" wrote:

Oh my mistake, you should be looking for the last line's presentation group
element like this:
xmlDoc.DocumentElement.SelectSingleNode("//Line[last()]/PresentationGroup")
or
xmlDoc.DocumentElement.SelectSingleNode("/Form/Content/Line[last()]/PresentationGroup[last()]")
--
HTH,
Phillip Williams
http://www.societopia.net
http://www.webswapp.com
"Joe" wrote:

Phillip,

I have tried both of these. For some reason each returns the first
PresentationGroup. Any idea why?

--
Joe
"Phillip Williams" wrote:

xmlDoc.DocumentElement.SelectSingleNode("//PresentationGroup[last()]")
or
xmlDoc.DocumentElement.SelectSingleNode("/Form/Content/Line/PresentationGroup[last()]")
--
HTH,
Phillip Williams
http://www.societopia.net
http://www.webswapp.com
"Joe" wrote:

> Hello All:
>
> I have an xml document with the following structure, where Form is the
> document element:
>
> <Form>
> <Content>
> <Line>blah blah blah</Line>
> <Line>
> <PresentationGroup>
> miscellaneous tags
> </PresentationGroup>
> </Line>
> <Line>blah blah blah 2</Line>
> <Line>
> <PresentationGroup>
> miscellaneous tags
> </PresentationGroup>
> </Line>
> </Content>
> </Form>
>
> I want an XPath to the last PresentationGroup node (there are multiple
> PresentationGroup nodes per xml document and the number of PresentationGroup
> nodes per document changes from one document to the next). I've tried
> "Content/Line/PresentationGroup[last()]" and am getting nothing.
>
> My code looks like:
>
> xmlDoc.DocumentElement.SelectSingleNode("Content/Line/PresentationGroup[last()]")
>
> This returns Nothing. I can't figure out why, although I'm sure that it's
> simple!
>
> Can anyone see what I am doing wrong?
>
> TIA,
> --
> Joe

[Phillip Williams]

The SelectSingleNode would find the first matched presentationGroup that is
the last within its parent element. You are then looking for to get a list of
all presentationGroups and pickup the last one in the list like this:

Dim xnl As XmlNodeList =
xmlDoc.DocumentElement.SelectNodes("//PresentationGroup")
Dim xe As XmlNode = xnl.Item(xnl.Count - 1)

--
HTH,
Phillip Williams
http://www.societopia.net
http://www.webswapp.com
"Joe" wrote:

I'm not looking for the last line's presentation group; I'm looking for the
last presentation group. I do know that the last one will be in a Line node,
but it will not be in the last Line node.

--
Joe
"Phillip Williams" wrote:

Oh my mistake, you should be looking for the last line's presentation group
element like this:
xmlDoc.DocumentElement.SelectSingleNode("//Line[last()]/PresentationGroup")
or
xmlDoc.DocumentElement.SelectSingleNode("/Form/Content/Line[last()]/PresentationGroup[last()]")
--
HTH,
Phillip Williams
http://www.societopia.net
http://www.webswapp.com
"Joe" wrote:

Phillip,

I have tried both of these. For some reason each returns the first
PresentationGroup. Any idea why?

--
Joe
"Phillip Williams" wrote:

>
> xmlDoc.DocumentElement.SelectSingleNode("//PresentationGroup[last()]")
> or
> xmlDoc.DocumentElement.SelectSingleNode("/Form/Content/Line/PresentationGroup[last()]")
>
>
> --
> HTH,
> Phillip Williams
> http://www.societopia.net
> http://www.webswapp.com
>
>
> "Joe" wrote:
>
> > Hello All:
> >
> > I have an xml document with the following structure, where Form is the
> > document element:
> >
> > <Form>
> > <Content>
> > <Line>blah blah blah</Line>
> > <Line>
> > <PresentationGroup>
> > miscellaneous tags
> > </PresentationGroup>
> > </Line>
> > <Line>blah blah blah 2</Line>
> > <Line>
> > <PresentationGroup>
> > miscellaneous tags
> > </PresentationGroup>
> > </Line>
> > </Content>
> > </Form>
> >
> > I want an XPath to the last PresentationGroup node (there are multiple
> > PresentationGroup nodes per xml document and the number of PresentationGroup
> > nodes per document changes from one document to the next). I've tried
> > "Content/Line/PresentationGroup[last()]" and am getting nothing.
> >
> > My code looks like:
> >
> > xmlDoc.DocumentElement.SelectSingleNode("Content/Line/PresentationGroup[last()]")
> >
> > This returns Nothing. I can't figure out why, although I'm sure that it's
> > simple!
> >
> > Can anyone see what I am doing wrong?
> >
> > TIA,
> > --
> > Joe

[Joe]

Je vous remercie.
--
Joe
"Phillip Williams" wrote:

The SelectSingleNode would find the first matched presentationGroup that is
the last within its parent element. You are then looking for to get a list of
all presentationGroups and pickup the last one in the list like this:

Dim xnl As XmlNodeList =
xmlDoc.DocumentElement.SelectNodes("//PresentationGroup")
Dim xe As XmlNode = xnl.Item(xnl.Count - 1)

--
HTH,
Phillip Williams
http://www.societopia.net
http://www.webswapp.com
"Joe" wrote:

I'm not looking for the last line's presentation group; I'm looking for the
last presentation group. I do know that the last one will be in a Line node,
but it will not be in the last Line node.

--
Joe
"Phillip Williams" wrote:

Oh my mistake, you should be looking for the last line's presentation group
element like this:
xmlDoc.DocumentElement.SelectSingleNode("//Line[last()]/PresentationGroup")
or
xmlDoc.DocumentElement.SelectSingleNode("/Form/Content/Line[last()]/PresentationGroup[last()]")
--
HTH,
Phillip Williams
http://www.societopia.net
http://www.webswapp.com
"Joe" wrote:

> Phillip,
>
> I have tried both of these. For some reason each returns the first
> PresentationGroup. Any idea why?
>
> --
> Joe
>
>
> "Phillip Williams" wrote:
>
> >
> > xmlDoc.DocumentElement.SelectSingleNode("//PresentationGroup[last()]")
> > or
> > xmlDoc.DocumentElement.SelectSingleNode("/Form/Content/Line/PresentationGroup[last()]")
> >
> >
> > --
> > HTH,
> > Phillip Williams
> > http://www.societopia.net
> > http://www.webswapp.com
> >
> >
> > "Joe" wrote:
> >
> > > Hello All:
> > >
> > > I have an xml document with the following structure, where Form is the
> > > document element:
> > >
> > > <Form>
> > > <Content>
> > > <Line>blah blah blah</Line>
> > > <Line>
> > > <PresentationGroup>
> > > miscellaneous tags
> > > </PresentationGroup>
> > > </Line>
> > > <Line>blah blah blah 2</Line>
> > > <Line>
> > > <PresentationGroup>
> > > miscellaneous tags
> > > </PresentationGroup>
> > > </Line>
> > > </Content>
> > > </Form>
> > >
> > > I want an XPath to the last PresentationGroup node (there are multiple
> > > PresentationGroup nodes per xml document and the number of PresentationGroup
> > > nodes per document changes from one document to the next). I've tried
> > > "Content/Line/PresentationGroup[last()]" and am getting nothing.
> > >
> > > My code looks like:
> > >
> > > xmlDoc.DocumentElement.SelectSingleNode("Content/Line/PresentationGroup[last()]")
> > >
> > > This returns Nothing. I can't figure out why, although I'm sure that it's
> > > simple!
> > >
> > > Can anyone see what I am doing wrong?
> > >
> > > TIA,
> > > --
> > > Joe

[Phillip Williams]

You are welcome.
--
Phillip Williams
http://www.societopia.net
http://www.webswapp.com
"Joe" wrote:

Je vous remercie.
--
Joe
"Phillip Williams" wrote:

The SelectSingleNode would find the first matched presentationGroup that is
the last within its parent element. You are then looking for to get a list of
all presentationGroups and pickup the last one in the list like this:

Dim xnl As XmlNodeList =
xmlDoc.DocumentElement.SelectNodes("//PresentationGroup")
Dim xe As XmlNode = xnl.Item(xnl.Count - 1)

--
HTH,
Phillip Williams
http://www.societopia.net
http://www.webswapp.com
"Joe" wrote:

I'm not looking for the last line's presentation group; I'm looking for the
last presentation group. I do know that the last one will be in a Line node,
but it will not be in the last Line node.

--
Joe
"Phillip Williams" wrote:

> Oh my mistake, you should be looking for the last line's presentation group
> element like this:
> xmlDoc.DocumentElement.SelectSingleNode("//Line[last()]/PresentationGroup")
> or
> xmlDoc.DocumentElement.SelectSingleNode("/Form/Content/Line[last()]/PresentationGroup[last()]")
> --
> HTH,
> Phillip Williams
> http://www.societopia.net
> http://www.webswapp.com
>
>
> "Joe" wrote:
>
> > Phillip,
> >
> > I have tried both of these. For some reason each returns the first
> > PresentationGroup. Any idea why?
> >
> > --
> > Joe
> >
> >
> > "Phillip Williams" wrote:
> >
> > >
> > > xmlDoc.DocumentElement.SelectSingleNode("//PresentationGroup[last()]")
> > > or
> > > xmlDoc.DocumentElement.SelectSingleNode("/Form/Content/Line/PresentationGroup[last()]")
> > >
> > >
> > > --
> > > HTH,
> > > Phillip Williams
> > > http://www.societopia.net
> > > http://www.webswapp.com
> > >
> > >
> > > "Joe" wrote:
> > >
> > > > Hello All:
> > > >
> > > > I have an xml document with the following structure, where Form is the
> > > > document element:
> > > >
> > > > <Form>
> > > > <Content>
> > > > <Line>blah blah blah</Line>
> > > > <Line>
> > > > <PresentationGroup>
> > > > miscellaneous tags
> > > > </PresentationGroup>
> > > > </Line>
> > > > <Line>blah blah blah 2</Line>
> > > > <Line>
> > > > <PresentationGroup>
> > > > miscellaneous tags
> > > > </PresentationGroup>
> > > > </Line>
> > > > </Content>
> > > > </Form>
> > > >
> > > > I want an XPath to the last PresentationGroup node (there are multiple
> > > > PresentationGroup nodes per xml document and the number of PresentationGroup
> > > > nodes per document changes from one document to the next). I've tried
> > > > "Content/Line/PresentationGroup[last()]" and am getting nothing.
> > > >
> > > > My code looks like:
> > > >
> > > > xmlDoc.DocumentElement.SelectSingleNode("Content/Line/PresentationGroup[last()]")
> > > >
> > > > This returns Nothing. I can't figure out why, although I'm sure that it's
> > > > simple!
> > > >
> > > > Can anyone see what I am doing wrong?
> > > >
> > > > TIA,
> > > > --
> > > > Joe

[Martin Honnen]

Joe wrote:

I'm not looking for the last line's presentation group; I'm looking for the
last presentation group. I do know that the last one will be in a Line node,
but it will not be in the last Line node.

Then

xmlDocument.DocumentElement.SelectSingleNode(@"(Co ntent/Line/PresentationGroup)[last()]")

should do.

--

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