Retrieving values from XML file

[Mike]

I want to be able access an xml file using an XPath? query to go to a
specific node. Once I have that node I want to be able to retrieve the value
of an attribute. Can't seem to get this working using the 2.0 Framework.
Here's a sample of the XML

<Agency>

<vu_Agency AgencySysNo="1" Name="Dept 1"/>

<vu_Agency AgencySysNo="2" Name="Dept 2"/>

</Agency>
The code I'm playing with is...

Dim document As XPathDocument = New
XPathDocument(ConfigurationManager.AppSettings("xm lPath").ToString() &
"Agency.xml")

Dim navigator As XPathNavigator = document.CreateNavigator()

Dim agencySysNo As Integer = 2

Dim exp As XPathExpression =
navigator.Compile("/Agency/vu_Agency[@AgencySysNo=" & agencySysNo & "]")

Dim nodes As XPathNodeIterator

nodes = navigator.Select(exp)

Dim nodesNavigator As XPathNavigator = nodes.Current

Dim nodesText As XPathNodeIterator =
nodesNavigator.SelectDescendants(XPathNodeType.Tex t, True)

Response.Write(nodesText.Current.Value)

Thanks for any help....

--
Mike Gasperino
Sr. Software Developer
office: 919-807-2310

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[Pascal Schmitt]

Hello!

Try this (it is C#, I'm not sure of the VB syntax :o)

....
XPathExpression exp =
navigator.Compile(string.Format("/Agency/vu_Agency[@AgencySysNo='{0}']/@Dept",
agencySysNo ));

XmlNode n = navigator.SelectSingleNode( exp )
if( n != null )
Response.Write( ((XmlAttribute) n).Value );
The XPath Expression directly selects the Attribute (I suppose it is
unique?) and returns null/Nothing if it wasn't found. If it retourned
something, it is the Attribute, so I cast it as an XmlAttribute and
return its Value.
--
Pascal Schmitt

[Mike]

Hey Pascal,

I get a pre-compile message on this line of code "XmlNode n =
navigator.SelectSingleNode( exp )"

Value of type 'System.Xml.XPath.XPathNavigator' cannot be converted to
'System.Xml.XmlNode'.

How do I convert to a xmlnode?

Thanks
"Pascal Schmitt" <ne*******@cebra.nu> wrote in message
news:OZ**************@TK2MSFTNGP14.phx.gbl...

Hello!

Try this (it is C#, I'm not sure of the VB syntax :o)

...
XPathExpression exp =
navigator.Compile(string.Format("/Agency/vu_Agency[@AgencySysNo='{0}']/@Dept",
agencySysNo ));

XmlNode n = navigator.SelectSingleNode( exp )
if( n != null )
Response.Write( ((XmlAttribute) n).Value );
The XPath Expression directly selects the Attribute (I suppose it is
unique?) and returns null/Nothing if it wasn't found. If it retourned
something, it is the Attribute, so I cast it as an XmlAttribute and return
its Value.
--
Pascal Schmitt

[Martin Honnen]

Mike wrote:

I get a pre-compile message on this line of code "XmlNode n =
navigator.SelectSingleNode( exp )"

Value of type 'System.Xml.XPath.XPathNavigator' cannot be converted to
'System.Xml.XmlNode'.

If you have an XPathNavigator then there is (at least in .NET 1.x) no
SelectSingleNode method, there is a Select method however so you are
likely looking for something as

XPathNodeIterator iterator = navigator.Select(exp);
while (iterator.MoveMext()) {
// access iterator.Current here
}
--

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