Re: [xsl] XPATH total count of multiple child nodes

[Wendell Piez <wapiez@xxxxxxxxxxxxxxxx>]

Edward,

At 01:22 PM 5/3/2005, you wrote:
> My new problem is that I am trying to build a conditional statement based 
> on a count of the number of child elements. There is an element "dates" 
> that contains child elements containing particular dates. Normally, I 
> would use something like:
>
> Check if any of them exisit at all...
>
> <xsl:if test="(filed) or (decided) or (submitted) or (revised) or (term)">
>
> then, see if there is more than one of them ...
>
> <xsl:if test="count(date) > 1">
>
> However, the child elements do not all have the same name. They can have 
> one of five different names (filed, decided, submitted, revised, or term), 
> which may appear in almost any combination. There are no other child 
> elements, so I was hoping there was a simple way to count the total number 
> of child elements without specifying them by name?

Sure, that's simply "child::*" ("*" is a node test that matches any 
element, or more correctly, any element except when on the attribute and 
namespace axes, wherein it matches an attribute or a namespace node), which 
is long for "*". So you need

<xsl:match="dates">
  ... whatever you do for the wrapper if anything ...
  <xsl:if test="*">
    ... whatever you do now you know there are children ...
  </xsl:if>
</xsl:match>

Note that ordinarily we don't have to conduct this test, however, since 
apply-templates just traverses to whatever child elements we have (or 
actually, to child nodes of any type). There are cases, however, when you 
may have

<dates></dates>

and you want to distinguish that case. You can also test="not(*)" which 
will be true if you *don't* have any child elements.

Similarly, count(*) returns a number representing how many child elements 
you have, so you could test="count(*) > 2" which tests true when there are 
three or more element children.

If you also need to test for comments or processing instructions, another 
node test is "node()" -- in XPath, child::node() will return all child 
nodes of whatever type, not just elements.

Enjoy,
Wendell


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Wendell Piez                            mailto:wapiez@xxxxxxxxxxxxxxxx
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