XSLTProcessor::registerPHPFunctions

(PHP 5 >= 5.0.4, PHP 7, PHP 8)

XSLTProcessor::registerPHPFunctions — Enables the ability to use PHP functions as XSLT functions

Description

public XSLTProcessor::registerPHPFunctions(array|string|null $functions = null): void

This method enables the ability to use PHP functions as XSLT functions within XSL stylesheets.

Parameters

functions

Use this parameter to only allow certain functions to be called from XSLT.

This parameter can be either a string (a function name) or an array of functions.

Return Values

No value is returned.

Examples

Example #1 Simple PHP Function call from a stylesheet

<?php
$xml = <<<EOB
<allusers>
 <user>
  <uid>bob</uid>
 </user>
 <user>
  <uid>joe</uid>
 </user>
</allusers>
EOB;
$xsl = <<<EOB
<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="1.0" 
     xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
     xmlns:php="http://php.net/xsl">
<xsl:output method="html" encoding="utf-8" indent="yes"/>
 <xsl:template match="allusers">
  <html><body>
    <h2>Users</h2>
    <table>
    <xsl:for-each select="user">
      <tr><td>
        <xsl:value-of
             select="php:function('ucfirst',string(uid))"/>
      </td></tr>
    </xsl:for-each>
    </table>
  </body></html>
 </xsl:template>
</xsl:stylesheet>
EOB;
$xmldoc = new DOMDocument();
$xmldoc->loadXML($xml);
$xsldoc = new DOMDocument();
$xsldoc->loadXML($xsl);

$proc = new XSLTProcessor();
$proc->registerPHPFunctions();
$proc->importStyleSheet($xsldoc);
echo $proc->transformToXML($xmldoc);
?>

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User Contributed Notes 20 notes

down

heinemann dot juergen at hjcms dot de ¶

18 years ago

You can find mor Examples at PHP Sources php-5.*/ext/xsl/tests
<?php

$xform = <<<EOT
<?xml version = '1.0' encoding = 'utf-8' ?>
<xsl:stylesheet version="1.0"
    xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
    xmlns:php="http://php.net/xsl"
    xsl:extension-element-prefixes="php"
>
<xsl:output method="xml" indent="yes" encoding="utf-8" />
<xsl:namespace-alias stylesheet-prefix="php" result-prefix="xsl" />
<xsl:template match="root">
<html>
<head>
    <title>Dateformat</title>
</head>
<body>
<xsl:for-each select="datenode">
    <li>
        <xsl:value-of select="php:functionString('convertDate', . )" />
    </li>
    </xsl:for-each>
</body>
</html>
</xsl:template>
</xsl:stylesheet>
EOT;

function convertDate( $i )
{
    setlocale( LC_TIME, 'de_DE' );
    return utf8_encode( strftime( '%B %d %A %Y %H:%M:%S CET', $i ) );
}

$xsl = new XSLTProcessor;
$xsl->registerPHPFunctions();
$xsl->setParameter( 'DOCTYPE', 'PUBLIC', 'http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd' );
$xsl->setParameter( 'html', 'xmlns', 'http://www.w3.org/1999/xhtml' );

$xdom = new DomDocument( '1.0', 'utf-8' );
$xdom->loadXML( $xform );

$xsl->importStyleSheet( $xdom );
unset( $xdom );

$dom = new DomDocument( '1.0', 'utf-8' );
$r = $dom->appendChild( $dom->createElement( 'root' ) );
foreach ( range( 1, 12 ) AS $i ) {
    $r->appendChild( $dom->createElement( 'datenode', mktime( date('G'), date('i'), date('s'), $i, date('d'), date('Y') ) ) );
}

header( "Content-Type: text/html; charset=utf-8;" );
header( "Content-Encoding: utf-8" );
echo $xsl->transformToXML( $dom );

?>

down

Matthew, info at mathias-schaefer dot de ¶

13 years ago

=> there is no instance of your class needed, you have to take care about the namespace (using 5.3).

<!-- xsl:
<xsl:value-of select="php:function ('My\Name\Space\MyClassName::methodName',1+2)"/>
--->

<?php
namespace My\Name\Space;

   class MyClassName
   {
      static public function methodName($someArgument)
      {
         return "resultis:".$someArgument;
      }
   }
?>

<!-- result:
resultis:3
-->

=> no to-string conversion of the argument needed
=> returning numbers is also possible (maybe DOM nodes too)

Keep on hackin'

down

taylorbarstow at that google mail thingy ¶

18 years ago

Add-on to my previous note (below) about returning nodesets to XSLT from PHP functions:

You don't have to return a DOMDocument, DOMElement works just as well.  Plus, retuning a DOMElement gets around the problem of discarding the root node which I discuss below and which is also touched on by "Ingram".

down

Ingram ¶

18 years ago

Upon testing returning of a nodeset contributed by

taylorbarstow at that google mail thingy

(which works excellently, TY!)

I found that with using:

===
"Presumably, it's worth creating a template to do the discard:

<xsl:template select="*" mode="discardRoot">
   <xsl:apply-templates select="./*" />
</xsl:template>

Which you can call like so:

<xsl:apply-templates select="php:function('getNodeSet')" mode="discardRoot" /> "
===

I could only output the text and not any of the tags after applying templates - i.e. it stripped all elements around text.

Instead using:

===
<xsl:template match="/">
   <xsl:for-each select="php:function('getNodeSet')" />
     <xsl:apply-templates />
   </xsl:for-each>
</xsl:template>

which effectively discards the root node. 
===

Worked fine and allowed me to apply-templates without problem on the returned nodeset.

down

hopeseekr at gmail dot com ¶

18 years ago

One of the peskiest things I had problems with was encoding URL parameters.  I mean, pretend you want to populate a link with "search+terms" instead of just "search terms".  I was including two seperate URLs in the XML and that was ludicrous. 

Below is a far more elegant PHP+XSLT solution.  You will also see it uses two *undocumented* features of registerPHPFunctions(), namely php:functionString() and the passing of parameters to the function.  I figured this out by trial and error; I really hope this note helps you as it *greatly* expands the power of php functions in XSLT!

<?php
/* --- XML input --- */
<search_results>
   <query>concert tickets</query>
</search_results>

/* --- XSL code --- */
<!-- Display query -->
<xsl:template match="search_results">
   <!-- Get URL-encoded string via PHP -->
   <xsl:variable name="safeurl" as="xs:string" select="php:functionString('urlencode', query)" />
   <p>Your search for <em><xsl:value-of select="query"/></em> can be continued at <a href="http://www.tixtix.com/search.php?q={$safeurl}">our search engine</a></p>
</xsl:template>

/* --- XHTML output --- */
<p>Your search for <em>concert tickets</em> can be continued at <a href="http://www.tixtix.com/search.php?q=space+cowboy">our search engine</a></p>
?>

Cool, huh?

down

taylorbarstow at that google mail thingy ¶

18 years ago

From a PHP function, you can pass a nodeset back to XSL using a DOMDocument.  For example:

<?php

function getNodeSet() {
   $xml = 
       "<test>" .
       "<a-node>This is a node</a-node>" .
       "<a-node>This is another node</a-node>" .
       "</test>";
   $doc = new DOMDocument;
   $doc->loadXml($xml);
   return $doc;
}

?>

The only problem I've found is that the root level node in your returned DOM document acts like the root level node of your original.   SO, it's easy to introduce an infinite loop like so:

<xsl:template match="/">
   <xsl:apply-templates select="php:function('getNodeSet')" />
</xsl:template>

To avoid this, I've been using a construct like:

<xsl:template match="/">
   <xsl:for-each select="php:function('getNodeSet')" />
      <xsl:apply-templates />
   </xsl:for-each>
</xsl:template>

which effectively discards the root node.  Presumably, it's worth creating a template to do the discard:

<xsl:template select="*" mode="discardRoot">
   <xsl:apply-templates select="./*" />
</xsl:template>

Which you can call like so:

<xsl:apply-templates select="php:function('getNodeSet')" mode="discardRoot" />

down

zac at zacbowling dot com ¶

20 years ago

One thing I have told a lot of people to do if they are having 
issues with this function is to check for any 'xmlns' attributes 
that get generated and added to your xml pages by some 
types of popular software. 

<?php 
$file = "http://data.map***.net/m***ck.asmx/GetMessages?IMEI=$id";

$docxml = file_get_contents($file);

//You may have to do something like this where 
//I remove any instance of xmlns tags that get
//returned by my ASP.NET SOAP responses.

$docxml = 
 str_replace("xmlns=\"http://data.map***.net/m***ck.asmx?WSDL\"",
  "",$docxml);

$xslt = new xsltProcessor;

//You don't remove them then this function will blow up. 
$xslt->registerPHPFunctions();
$xslt->importStyleSheet(DomDocument::load('../xsl/message.xsl'));
print $xslt->transformToXML(DomDocument::loadXML($docxml));

?>

Also a few cool tricks with this function is that you can call 
built in PHP functions. For example:

<xsl:value-of 
  select="php:function('nl2br',string(MessageContent/Message))" 
  disable-output-escaping="yes"/>

That XSL value will now return your normal string but replace
all your new line charactors in your xml with '<br />'s.

Also note the 'disable-output-escaping="yes"' statement. If 
you don't call this, then the output of that bind will be ran 
thru basicly a "htmlencode()" type function. 

Last but not least, take a look at the 'string()' function I 
called in XSL before passing it back. That is because without 
calling that, when it runs it will try and pass the node object, 
and not its value (which is what you most likely only want).

This function is very awsome and could lead to some very 
interesting code development. Skins could be loaded 
remotely. You could write an RSS viewer in PHP without much 
code. You could parse XHTML pages into another view (either 
localy or remotely). Then you can take that same XML 
content and throw it against ASP.NET, Java, or even a 
command line processing tool using that same exact XSL 
style sheet and generate the front ends for you page without 
much change. I'm very excited. 

Happy codding.

down

zac at zacbowling dot com ¶

20 years ago

One thing to note about this function. A lot of values need to be converted to a XSLT string using the "string()" function in XLS before you pass them to your functions, and when you return them make sure that if they are strings that you call the "strval()" in php before doing so. This saved me hours. 

Hope that helps.

Zac Bowling

down

Demerit ¶

14 years ago

Let's get the terminology correct here, folks.



If you are calling a function that is residing within a class, reference it by its INSTANCE name, NOT its class name.



class.my_class.php:



<?php

class class_name {

static function function_name($in){

return ($out);

}

}

?>



calling_document.php:



<?php

require_once('class.my_class.php');

$instance_name=new class_name();

?>



my_xslt.xsl:



<xsl:value-of select="php:function ('instance_name::function_name','garbage')" />



BTW, in 5.1.6 double-colon (::) is the only thing that works when calling a function that resides within a class. However, you must declare your function as static. Using -> as some have suggested (e.g., php:function ('instance_name->function_name','garbage')) doesn't work at all, no matter how you declare your function.

down

Ariz Jacinto ¶

16 years ago

If you want to use replace() function similar to XPath 2.0[1]  and you want to avoid a long XSLT function similar to this one[2], you can use PHP's str_replace() instead:

   <xsl:value-of select="php:functionString('str_replace','pattern', 'replacement' , . )">

Links:
  [1] http://www.w3.org/TR/2004/WD-xpath-functions-20041029/#func-replace
  [2] http://aspn.activestate.com/ASPN/Cookbook/XSLT/Recipe/65426

_

down

thsoft at vipmail dot hu ¶

16 years ago

Unfortunately, you can't pass arrays to PHP from XLST.
But you can pass an arbitrary number of arguments to a PHP function and then get them with func_get_args() as an array.
[There's no sense writing a function that is identical to the array() construct, because a function's return value is converted to a string when passed as an argument to another function. This means deep arrays cannot be handled this way.]

down

junkmail at eighteyes dot com ¶

20 years ago

When writing a stylesheet that uses a callback function be sure to include a namespace declaration for php, as follows: 

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:php="http://php.net/xsl" version='1.0'>

down

begemot at php dot com dot ua ¶

20 years ago

I think it help  your.
<?php

function dateLang () {
        return strftime("%A");
}

$xsl = new DomDocument();
$xsl->load("datetime.xsl");
$inputdom = new DomDocument();
$inputdom->load("today.xml");

$proc = new XsltProcessor();
$proc->registerPhpFunctions();

// Load the documents and process using $xslt
$xsl = $proc->importStylesheet($xsl);

/* transform and output the xml document */
$newdom = $proc->transformToDoc($inputdom);

print $newdom->saveXML();

?>

Here's the XSLT stylesheet, datetime.xsl, that will call that function:

<?xml version="1.0" encoding="iso-8859-1" ?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:php="http://php.net/xsl">
<xsl:template match="/">
  <xsl:value-of select="php:function('dateLang')" />
</xsl:template>
</xsl:stylesheet>

And here's an absolute minimal XML file, today.xml, to pass through the stylesheet (although articles.xml would achieve the same result):

<?xml version="1.0" encoding="iso-8859-1" ?>
<today></today>

down

Nic Luciano ¶

15 years ago

Ritch said "If you wish to use a function from inside a class use the double colon (::) notation..."

Also note that the class function must be declared as static.

down

thsoft at vipmail dot hu ¶

17 years ago

The correct way to receive DOM nodes (let it be element, document, document fragment etc.) returned from PHP is to use <xsl:copy-of select="php:function...

I found the idea and an example here: http://bugs.php.net/bug.php?id=29409

For the technical details about the reason, see http://www.w3.org/TR/xslt#copy-of

down

phil at worldpoolfederation dot com ¶

17 years ago

Not true

Use :: to call static functions
Use -> to call non static functions

You must define a function as static in php 5.1 to be able to call it statically.

down

mark at thirst dot org ¶

18 years ago

Ritch said "If you wish to use a function from inside a class use the double colon (::) notation..."   This worked in 5.0.4 but no longer works in 5.1.6.

down

franp at free dot fr ¶

18 years ago

Note that if you want your output to validate against some xhtml dtd, you must add the following attribute to the xsl:stylesheet element of the xslt stylesheet :
exclude-result-prefixes="php".

Otherwise, you get an "invalid attribute xmlns:php" error.

down

benbarnett ¶

19 years ago

You can use the php:functionString() in the XSL, which will automatically convert output to a string!

down

-1

Ritch at Bugsoftware dot co dot uk ¶

19 years ago

If you wish to use a function from inside a class use the double colon (::) notation, for example;

php:functionString('classname::function')

The funtion is fired off as a static and as such acts like a function in the global namespace.

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