Did I miss something here ?

[Sonu Kapoor]

Ok guys, I could bang my head on the laptop, cause I dont
get this to work. The scanrio: I am tryting to pass an
parameter with the help of XslTransform to the xsl file.
But whenever I run the code, I got the error:

System.Xml.XPath.XPathException: Expression must evaluate
to a node-set.

Maybe somebody can help me out here:

my xml file:

<?xml version="1.0" encoding="utf-8"?>
<CategoryList>
<Category>
<MainCategory>1</MainCategory>
<Description>This is a list my XML
articles.</Description>
<Active>true</Active>
</Category>
<Category>
<MainCategory>2</MainCategory>
<Description>This is a list my XML
articles.</Description>
<Active>true</Active>
</Category>
<Category>
<MainCategory>3</MainCategory>
<Description>This is a list my XML
articles.</Description>
<Active>true</Active>
</Category>
</CategoryList>

my xsl file:

<?xml version="1.0"?>
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:param name="strXPath" />

<xsl:template match="/">
<xsl:apply-templates select="$strXPath" />
</xsl:template>

<xsl:template match="Category">
<xsl:copy-of select="." />
</xsl:template>
</xsl:stylesheet>

my code:

XmlDocument xmlDoc= new XmlDocument();
xmlDoc.Load(Server.MapPath("categories.xml"));

XslTransform xslt = new XslTransform();
xslt.Load(Server.MapPath("categories.xslt"));

XPathNavigator nav = xmlDoc.CreateNavigator();

XsltArgumentList arguments = new XsltArgumentList();
arguments.AddParam("strXPath", "", nav.Select
("//Category/MainCategory"));

MemoryStream ms = new MemoryStream();
xslt.Transform( nav, null, ms, null);
ms.Seek( 0, SeekOrigin.Begin );

StreamReader sr = new StreamReader(ms);

//Print out the result
Response.Write(sr.ReadToEnd());

Thanks, Sonu

[Sonu Kapoor]

I solved the problem. The problem was that I forgot to
pass the parameters.

here is the line:
xslt.Transform( nav, null, ms, null);

This should be changed to:
xslt.Transform( nav, arguments, ms, null);

Sonu

-----Original Message-----
Ok guys, I could bang my head on the laptop, cause I dont
get this to work. The scanrio: I am tryting to pass an
parameter with the help of XslTransform to the xsl file.
But whenever I run the code, I got the error:

System.Xml.XPath.XPathException: Expression must evaluate
to a node-set.

Maybe somebody can help me out here:

my xml file:

<?xml version="1.0" encoding="utf-8"?>
<CategoryList>
<Category>
<MainCategory>1</MainCategory>
<Description>This is a list my XML
articles.</Description>
<Active>true</Active>
</Category>
<Category>
<MainCategory>2</MainCategory>
<Description>This is a list my XML
articles.</Description>
<Active>true</Active>
</Category>
<Category>
<MainCategory>3</MainCategory>
<Description>This is a list my XML
articles.</Description>
<Active>true</Active>
</Category>
</CategoryList>

my xsl file:

<?xml version="1.0"?>
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:param name="strXPath" />

<xsl:template match="/">
<xsl:apply-templates select="$strXPath" />
</xsl:template>

<xsl:template match="Category">
<xsl:copy-of select="." />
</xsl:template>
</xsl:stylesheet>

my code:

XmlDocument xmlDoc= new XmlDocument();
xmlDoc.Load(Server.MapPath("categories.xml"));

XslTransform xslt = new XslTransform();
xslt.Load(Server.MapPath("categories.xslt"));

XPathNavigator nav = xmlDoc.CreateNavigator();

XsltArgumentList arguments = new XsltArgumentList();
arguments.AddParam("strXPath", "", nav.Select
("//Category/MainCategory"));

MemoryStream ms = new MemoryStream();
xslt.Transform( nav, null, ms, null);
ms.Seek( 0, SeekOrigin.Begin );

StreamReader sr = new StreamReader(ms);

//Print out the result
Response.Write(sr.ReadToEnd());

Thanks, Sonu
.