I have an xml document with a section roughly like this:
<a>
<b></b>
<b>Previous</b>
<b></b>
...
</a>
<a>
<b></b>
<b>Current</b>
<b></b>
...
</a>
...
I have the following section in my xsl:
<xsl:template match="/">
<xsl:apply-templates select="//a"/>
</xsl:template>
<xsl:template match="//a">
<xsl:for-each select="./b[text() != ???]">
...
</xsl:for-each>
</xsl:template>
I need the ??? to select the "c" element that is in the same position (within its parent "a" element) as the current "c" but in the previous "a" element (an example pair are marked as Current and Previous in the xml source).
Essentially this requires passing the position() of the for-each loop to its own select statement. This sounds kind of impossible - as the select statement is only evaluated once.
Now it would be possible to pass the position() from within the for-each loop and save it to a variable which could then be used in an if statement. However, the snag is I want to know when the last iteration has taken place. If I use an if statement then this breaks the meaning of last() - if the last iteration fails the if test.
Try this:
<xsl:for-each select="/b[ text() != ../../preceding-sibling::a/b[position(.)] ]" >
the preceding-sibling:: axis selects the node before the current step
Related
I'm new to xslt 2.0, I would like to set the value to a variable in for-each loop only once (means if the value set, I want to come out of the loop).
For now it keep iterating for all the users. I just want to come out of the loop once the value set (immediately after my first attemp). I'm not sure how to break if the value set once.
Can you please help me on the below code ?
XSLT Code:
<xsl:variable name="v_first_name">
<xsl:for-each select="$emailList/emails/child::*">
<xsl:variable name="mailid" select="id" />
<xsl:for-each select="$userList/users/child::*">
<xsl:if test="emailid = $mailid">
<xsl:if test="firstname eq 'Antony'">
<xsl:value-of select="firstname" />
</xsl:if>
</xsl:if>
</xsl:for-each>
</xsl:for-each>
</xsl:variable>
<xsl:if test="$v_first_name != ''">
<first_name>
<xsl:value-of select="$v_first_name" />
</first_name>
</xsl:if>
XML O/p:
<first_name>AntonyAntonyAntonyAntony</first_name>
Expected XML O/P:
<first_name>Antony</first_name>
Note1: Please note that I'm using xslt 2.0 and my lists can have duplicates (So Antony can come twice, but I want only once (or unique)).
Note2: I also tried with position(), but couldn't find it work as the condition () can match at any position.
Thanks in advance.
Start with XPath and simply select the nodes you are looking for instead of considering for-each a "loop". If you select e.g. $userList/users/*[emailid = $emailList/emails/*/id] you select child elements from users which have a matching emailid in $emailList/emails/*.
I am not sure which sense it makes to hard code a first name value and then output it but of course you can select e.g. $userList/users/*[emailid = $emailList/emails/*/id and firstname = 'Antony']/lastname. That gives you a sequence of element nodes, if you want the first use a positional predicate e.g. depending on the structure of your input $userList/users/*[emailid = $emailList/emails/*/id and firstname = 'Antony'][1]/lastname or, of all selected elements ($userList/users/*[emailid = $emailList/emails/*/id and firstname = 'Antony']/lastname)[1].
Originally: **How to apply XPath query to a XML variable typed as element()* **
I wish to apply XPath queries to a variable passed to a function in XSLT 2.0.
Saxon returns this error:
Type error at char 6 in xsl:value-of/#select on line 13 column 50 of stackoverflow_test.xslt:
XTTE0780: Required item type of result of call to f:test is element(); supplied value has item type text()
This skeleton of a program is simplified but, by the end of its development, it is meant to pass an element tree to multiple XSLT functions. Each function will extract certain statistics and create reports from the tree.
When I say apply XPath queries, I mean I wish to have the query consider the base element in the variable... if you please... as if I could write {count(doc("My XSLT tree/element variable")/a[1])}.
Using Saxon HE 9.7.0.5.
<?xml version="1.0" encoding="utf-8"?>
<xsl:stylesheet version="2.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:f="f:f">
<xsl:template match="/root">
<xsl:variable name="first" as="element()*">
<xsl:copy-of select="(./a[1])" />
</xsl:variable>
<html>
<xsl:copy-of select="f:test($first)" />
</html>
</xsl:template>
<xsl:function name="f:test" as="element()*">
<xsl:param name="frstElem" as="element()*" />
<xsl:value-of select="count($frstElem/a)" />
<!-- or any XPath expression -->
</xsl:function>
</xsl:stylesheet>
Some example data
<root>
<a>
<b>
<c>hi</c>
</b>
</a>
<a>
<b>
<c>hi</c>
</b>
</a>
</root>
Possibly related question: How to apply xpath in xsl:param on xml passed as input to xml
What you are doing is perfectly correct, except that you have passed an a element to the function, and the function is looking for an a child of this element, and with your sample data this will return an empty sequence.
If you want f:test() to return the number of a elements in the sequence that is the value of $frstElem, you can use something like
<xsl:value-of select="count($frstElem/self::a)" />
instead of using the (implicit) child:: axis.
I have a XPath that must match text and tags, except the tag <aa>; so,
./node()[name()!='aa']
is the correct xpath.
But it is insufficient for cases where tag aa is into the node, I need something like,
./node()[name()!='aa' and not(.//aa)]
but this xpath not works (!).
NOTE
I used
./*[not(self::aa or .//aa)] | ./text()
but it lost the original sequence order of the nodes. This problem is more evident when working with XSLT, example:
<xsl:for-each select="./*[not(self::aa or .//aa)] | ./text()">
<xsl:copy-of select="."/>
<xsl:for-each>
not works as expected (the order of nodes is not ensured). When using ./node() the order is always correct.
PS: with XSLT we have a solution using all the explained xpaths,
<xsl:for-each select="./node()[name()!='aa']">
<xsl:if test="not(.//aa)"><xsl:copy-of select="."/><xsl:if>
<xsl:for-each>
but the ideal/simplest one not works with the same result (when processing big and complex inputs),
<xsl:copy-of select="*[not(self::aa or .//aa)] | ./text()"/>
I'm imagining your file looks like:
<?xml version="1.0" encoding="UTF-8"?>
<root>
<aa/>
<b>
<aa/>
</b>
<c>
<b>
<aa/>
</b>
</c>
<d/>
<e>
<b/>
</e>
</root>
Then the expression
//node()[not(descendant-or-self::aa)]
returns all nodes (including the whitespace text nodes) that are not themselves an <aa> element or have an <aa> descendant. Children of <aa> are matched as well.
You'll probably want to do something like
<xsl:copy-of select="node()[not(descendant-or-self::aa)]"/>
I have a XML document with chapters and nested sections.
I am trying to find, for any section, the first second-level section ancestor.
That is the next-to-last section in the ancestor-or-self axis.
pseudo-code:
<chapter><title>mychapter</title>
<section><title>first</title>
<section><title>second</title>
<more/><stuff/>
</section>
</section>
</chapter>
my selector:
<xsl:apply-templates
select="ancestor-or-self::section[last()-1]" mode="title.markup" />
Of course that works until last()-1 isn't defined (the current node is the first section).
If the current node is below the second section, i want the title second.
Otherwise I want the title first.
Replace your xpath with this:
ancestor-or-self::section[position()=last()-1 or count(ancestor::section)=0][1]
Since you can already find the right node in all cases except one, I updated your xpath to also find the first section (or count(ancestor::section)=0), and then select ([1]) the first match (in reverse document order, since we are using the ancestor-or-self axis).
Here is a shorter and more efficient solution:
(ancestor-or-self::section[position() > last() -2])[last()]
This selects the last of the possibly first two topmost ancestors named section. If there is only one such ancestor, then it itself is the last.
Here is a complete transformation:
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="text"/>
<xsl:template match="section">
<xsl:value-of select="title"/>
<xsl:text> --> </xsl:text>
<xsl:value-of select=
"(ancestor-or-self::section[position() > last() -2])[last()]/title"/>
<xsl:text>
</xsl:text>
<xsl:apply-templates/>
</xsl:template>
<xsl:template match="text()"/>
</xsl:stylesheet>
When this transformation is applied on the following document (based on the provided, but added more nested section elements):
<chapter>
<title>mychapter</title>
<section>
<title>first</title>
<section>
<title>second</title>
<more/>
<stuff/>
<section>
<title>third</title>
</section>
</section>
</section>
</chapter>
the correct results are produced:
first --> first
second --> second
third --> second
I'm trying to select elements (a) with XPath 1.0 (or possibly could be with Regex) that are following siblings of particular element (b) but only preceed another b element.
<img><b>First</b><br>
<img> First Href - 19:30<br>
<img><b>Second</b><br>
<img> Second Href - 19:30<br>
<img> Third Href - 19:30<br>
I tried to make the sample as close to real world as possible. So in this scenario when I'm at element
<b>First</b>
I need to select
First Href
and when I'm at
<b>Second</b>
I need to select
Second Href
Third Href
Any idea how to achieve that? Thank you!
Dynamically create this XPath:
following-sibling::a[preceding-sibling::b[1][.='xxxx']]
where 'xxxx' is the replaced with the text of the current <b>.
This is assuming that all the elements actually are siblings. If they are not, you can try to work with the preceding and following axes, or you write a more specific XPath that better resembles document structure.
In XSLT you could also use:
following-sibling::a[
generate-id(preceding-sibling::b[1]) = generate-id(current())
]
Here is a solution which is just a single XPath expression.
Using the Kaysian formula for intersection of two nodesets $ns1 and $ns2:
$ns1[count(. | $ns2) = count($ns2)]
We simply substitute $ns1 with the nodeset of <a> siblings that follow the current <b> node, and we substitute $ns2 with the nodeset of <a> siblings that precede the next <b> node.
Here is a complete transformation that uses this:
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output omit-xml-declaration="yes" indent="yes"/>
<xsl:template match="/">
<xsl:apply-templates select="*/b"/>
</xsl:template>
<xsl:template match="b">
At: <xsl:value-of select="."/>
<xsl:variable name="vNextB" select="following-sibling::b[1]"/>
<xsl:variable name="vA-sAfterCurrentB" select="following-sibling::a"/>
<xsl:variable name="vA-sBeforeNextB" select=
"$vNextB/preceding-sibling::a
|
$vA-sAfterCurrentB[not($vNextB)]
"/>
<xsl:copy-of select=
"$vA-sAfterCurrentB
[count(.| $vA-sBeforeNextB)
=
count($vA-sBeforeNextB)
]
"/>
</xsl:template>
</xsl:stylesheet>
When this transformation is applied on the following XML document:
<t>
<img/>
<b>First</b>
<br />
<img/>
First Href - 19:30
<br />
<img/>
<b>Second</b>
<br />
<img/>
Second Href - 19:30
<br />
<img/>
Third Href - 19:30
<br />
</t>
the correct result is produced:
At: First First Href
At: Second Second Href
Third Href