Substrings from iterable node

3
votes

Please consider this sample file: http://www.w3schools.com/dom/books.xml

This XPath expression //title/text(), returns:

Everyday Italian
Harry Potter
XQuery Kick Start
Learning XML

Now I want just the first names, and try: tokenize(//title/text(),' ')[1], which returns:

Too many items

OTOH tokenize((//title/text())[1],' ')[1] returns first name for first node.

How can I get substrings with XPath while iterating nodes?

2
xpathxpath-2.0
theta, Was my answer useful to you or do you still have any problems? Did you notice that it is at least twice shorter than the currently accepted answer, and more efficient? - Dimitre Novatchev
Regards Dimitre. Thanks for you additional answer (which I up-voted), and for included tips and further explanation. It is very useful and I hope, others will soon up-vote, too. I already marked Cylian's answer as correct, as it showed me the mistake and lead me to //title/tokenize(text(),' ')[1] solution, which was perfect for my problem. Cheers - theta

2 Answers

2
votes

Use:

//text()/tokenize(.,' ')[1]

This produces a sequence of the first "word" of every text node in the XML document.

XSLT 2.0 - based verification:

<xsl:stylesheet version="2.0"   xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
    <xsl:output method="text"/>

 <xsl:template match="/">
     <xsl:sequence select="//text()/tokenize(.,' ')[1]"/>
 </xsl:template>
</xsl:stylesheet>

When this transformation is applied on the following XML document:

<t>
    <a>Everyday Italian</a>
    <b>Harry Potter</b>
    <c>XQuery Kick Start</c>
    <d>Learning XML</d>
</t>

the XPath expression is evaluated and the result of this evaluation is copied to the output:

 Everyday 
 Harry 
 XQuery 
 Learning

The above includes a few white-space only text nodes.

If you want to ignore any whitespace-only text node, change the XPath expression to:

//text()[normalize-space()]/tokenize(.,' ')[1]
1
votes

Try this

1. To get all parts except last one use this:

//title/string-join(tokenize(.,'\s+')[position() ne last()],' ')

or

2. To get only first one use this:

//title/string-join(tokenize(.,'\s+')[position() eq 1],' ')

Hope this helps.