XPath expression to select all XML child nodes except a specific list?
Here's the sample data:
<catalog>
<cd>
<title>Empire Burlesque</title>
<artist>Bob Dylan</artist>
<country>USA</country>
<customField1>Whatever</customField1>
<customField2>Whatever</customField2>
<customField3>Whatever</customField3>
<company>Columbia</company>
<price>10.90</price>
<year>1985</year>
</cd>
<cd>
<title>Hide your heart</title>
<artist>Bonnie Tyler</artist>
<country>UK</country>
<customField1>Whatever</customField1>
<customField2>Whatever</customField2>
<company>CBS Records</company>
<price>9.90</price>
<year>1988</year>
</cd>
<cd>
<title>Greatest Hits</title>
<artist>Dolly Parton</artist>
<country>USA</country>
<customField1>Whatever</customField1>
<company>RCA</company>
<price>9.90</price>
<year>1982</year>
</cd>
</catalog>
Say I want to select everything except the price and year elements. I would expect to write something like the below, which obviously doesn't work.
<?xml version="1.0" encoding="ISO-8859-1"?>
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:template match="/">
<html>
<body>
<xsl:for-each select="//cd/* except (//cd/price|//cd/year)"开发者_运维问答>
Current node: <xsl:value-of select="current()"/>
<br />
</xsl:for-each>
</body>
</html>
</xsl:template>
</xsl:stylesheet>
Please help me find a way to exclude certain child elements.
<xsl:for-each select="//cd/*[not(self::price or self::year)]">
But actually this is bad and unnecessarily complicated. Better:
<xsl:template match="catalog">
<html>
<body>
<xsl:apply-templates select="cd/*" />
</body>
</html>
</xsl:template>
<!-- this is an empty template to mute any unwanted elements -->
<xsl:template match="cd/price | cd/year" />
<!-- this is to output wanted elements -->
<xsl:template match="cd/*">
<xsl:text>Current node: </xsl:text>
<xsl:value-of select="."/>
<br />
</xsl:template>
Avoid <xsl:for-each>
. Almost all of the time it is the wrong tool and should be substituted by <xsl:apply-templates>
and <xsl:template>
.
The above works because of match expression specificity. match="cd/price | cd/year"
is more specific than match="cd/*"
, so it is the preferred template for cd/price
or cd/year
elements. Don't try to exclude nodes, let them come and handle them by discarding them.
I'd start experimenting with something like
"//cd/*[(name() != 'price') and (name() != 'year')]"
Or you just do normal recursive template matching with <xsl:apply-templates/>
, and then have empty templates for <price/>
and <year/>
elements:
<xsl:template match="price"/>
<xsl:template match="year"/>
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