Pass xsl:param to xsl:if

bonekrusher · September 6th, 2007, 11:41 AM

Hi,
I am building a search engine for my end uses that also would allow them to use XPATH to search the XML files.

I am writing the XSLT and was wondering if I can pass a Parameter to a xsl:if statement?

This returns a TRUE boolean even if its false:

Code:

    <xsl:param name="myxpath">//dispatch</xsl:param>

        <xsl:for-each select="document($xx)">
                                    <xsl:for-each select="/">
                                        <xsl:variable name="content" select="."/>
                                        <xsl:choose>
                                            <xsl:when test="$myxpath">
                                                <a href="{$mychap}">
                                                    <xsl:value-of select="//title"/>
                                                </a>
                                                <br/>
                                            </xsl:when>
                                        </xsl:choose>
                                    </xsl:for-each>

Thanks

mhkay · September 6th, 2007, 12:01 PM

You can certainly pass a parameter to xsl:if, but the value must be a boolean, not a string containing an XPath expression that can be evaluated to return a boolean!

The only way to evaluate XPath expressions contained in run-time strings is to use an extension function such as saxon:evaluate().

Michael Kay
http://www.saxonica.com/
Author, XSLT Programmer's Reference and XPath 2.0 Programmer's Reference

bonekrusher · September 6th, 2007, 12:12 PM

Michael,

As always. Thanks for the help.

Bones

samjudson · September 6th, 2007, 12:22 PM

Some XSLT processors do actually allow the passing of XPath expressions in as parameters (I'm thinking of AltovaXml specifically).

The following works:

altovaxml /xslt2 test.xsl /in test.xml /param myxpath="//dispatch"

however as Michael says, there is no way to do this from within a stylesheet.

/- Sam Judson : Wrox Technical Editor -/

mhkay · September 6th, 2007, 01:12 PM

Actually, I don't think it passes the expression itself as a parameter - it evaluates the expression and passes its result as the parameter value. But that may be enough for your needs.

Michael Kay
http://www.saxonica.com/
Author, XSLT Programmer's Reference and XPath 2.0 Programmer's Reference

bonekrusher · September 6th, 2007, 04:37 PM

Thanks Michael & Sam

I use XMLspy

As for Saxon:

Currently I use Saxon 8.8 with Kernow interface. My app is .NET. I have no clue on how to add an extension and use it within my XSLT. I Have both your books (XSLT 2.0 & XPATH 2.0) and will research tonight.

Thanks!