In his comment on my
last blog post Hendy wondered whether "instead of calling
the RenderMacroContent for another XSLT macro, it would be better
practice to include common XSLT directly?". I agree - he's right.
This is one aspect of XSLT that I'd come across in other people's
code (e.g. XSLTSearch) but hadn't gotten around to using myself.
It's a lot cleaner than using RenderMacroContent.
Here is the xslt which will be my reusable code which uses
ImageGen to output an image, given an imageId, and the
desired height and width of the image to display. Note the
<xsl-param bits - that's how you define your parameters in xslt
templates.
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE xsl:Stylesheet [ <!ENTITY nbsp " "> ]>
<xsl:stylesheet
version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:msxml="urn:schemas-microsoft-com:xslt"
xmlns:umbraco.library="urn:umbraco.library"
exclude-result-prefixes="msxml umbraco.library">
<xsl:output method="xml" omit-xml-declaration="yes"/>
<!-- General Purpose ImageGen ShowImage template, can be used anywhere on the site -->
<!-- Takes the id, height and width of the image as parameters and uses IMAGEGEN to display it -->
<xsl:template name="ShowImage">
<xsl:param name="imageId"></xsl:param>
<xsl:param name="width"></xsl:param>
<xsl:param name="height"></xsl:param>
<img>
<xsl:attribute name="src">
<xsl:text>/umbraco/ImageGen.ashx?image=</xsl:text>
<xsl:value-of select="umbraco.library:GetMedia($imageId,0)/data [@alias = 'umbracoFile']"/>
<xsl:text>&width=</xsl:text>
<xsl:value-of select="$width"/>
<xsl:text>&height=</xsl:text>
<xsl:value-of select="$height"/>
</xsl:attribute>
</img>
</xsl:template>
</xsl:stylesheet>
And here is one example of using the code. This could be on a
product page, to display the product image associated with the
current node (called 'image') with a given width as defined by the
parameter to the macro.
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE xsl:stylesheet [ <!ENTITY nbsp " "> ]>
<xsl:stylesheet
version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:msxml="urn:schemas-microsoft-com:xslt"
xmlns:umbraco.library="urn:umbraco.library"
exclude-result-prefixes="msxml umbraco.library">
<xsl:include href="ShowImageGenImage.xslt" mce_href="ShowImageGenImage.xslt"/>
<xsl:output method="xml" omit-xml-declaration="yes"/>
<xsl:param name="currentPage"/>
<xsl:param name="width" select="/macro/width"/>
<xsl:param name="height" select="/macro/height"/>
<!-- For use on the product page. Passes the image ID (alias is "image") of the current node to the -->
<!-- ShowImage xslt template to display it. Height and width values come from the macro parameters. -->
<xsl:template match="/">
<xsl:call-template name="ShowImage">
<xsl:with-param name="imageId" select="$currentPage/data[@alias='image']"/>
<xsl:with-param name="width" select="$width"/>
<xsl:with-param name="height" select="$height"/>
</xsl:call-template>
</xsl:template>
</xsl:stylesheet>
So there you have it. Two ways of re-using your xslt code. I'm
sure there are situations where one is preferable over the other,
but right now I think I'd lean towards this being the better of the
two.
David
