XSLT count items in array - arrays

Question

I'm trying to modify an XLST 1.0 file and I found that I can use an array like this:
<xsl:variable name="array">
<Item>106</Item>
<Item>107</Item>
</xsl:variable>
Now I want to write an IF structure where i have a test on the amount of items in the array.
I'v tried this, but this isn't working:
<xsl:if test="count($array) = 0"></xsl:if>
Am I using the right approach for this problem?

Answer 1

First, there are no "arrays" in XML.
Next, count($array) in your example will always return 1, because your variable contains a single parent node. To count the child Item nodes, you would need to use count($array/Item).
However, that too would fail, because in XSLT 1.0 your variable contains a result-tree-fragment - and XSLT 1.0 can only count nodes in a node-set.
One solution is to turn the RTF into a node-set, using an extension function (which is supported by practically all XSLT 1.0 processors). For example, the following stylesheet:
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:exsl="http://exslt.org/common"
extension-element-prefixes="exsl">
<xsl:output method="xml" version="1.0" encoding="UTF-8" indent="yes"/>
<xsl:variable name="array-rtf">
<Item>106</Item>
<Item>107</Item>
</xsl:variable>
<xsl:variable name="array" select="exsl:node-set($array-rtf)" />
<xsl:template match="/">
<test>
<xsl:value-of select="count($array/Item)"/>
</test>
</xsl:template>
</xsl:stylesheet>
returns:
<?xml version="1.0" encoding="UTF-8"?>
<test>2</test>
Another option is to use an internal element instead of a variable:
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:my="http://example.com/my"
exclude-result-prefixes="my">
<xsl:output method="xml" version="1.0" encoding="UTF-8" indent="yes"/>
<my:array>
<Item>106</Item>
<Item>107</Item>
</my:array>
<xsl:template match="/">
<test>
<xsl:value-of select="count(document('')/*/my:array/Item)"/>
</test>
</xsl:template>
</xsl:stylesheet>