(PHP 5)
XSLTProcessor::transformToXML — Transformierung zu einem XML-String
Transformiert die Quell-DOMNode unter Verwendung des mittels xsltprocessor::importStylesheet() importierten Stylesheets in einen String.
Die zu verarbeitende DOMNode.
Das Ergebnis der Transformierung als String oder FALSE im Fehlerfall.
Beispiel #1 Transformierung in einen String
<?php
// XML-Quellen laden
$xml = new DOMDocument;
$xml->load('collection.xml');
$xsl = new DOMDocument;
$xsl->load('collection.xsl');
// Prozessor instanziieren und konfigurieren
$proc = new XSLTProcessor;
$proc->importStyleSheet($xsl); // XSL Document importieren
echo $proc->transformToXML($xml);
?>
Das oben gezeigte Beispiel erzeugt folgende Ausgabe:
Hey! Welcome to Nicolas Eliaszewicz's sweet CD collection! <h1>Fight for your mind</h1><h2>by Ben Harper - 1995</h2><hr> <h1>Electric Ladyland</h1><h2>by Jimi Hendrix - 1997</h2><hr>
Entities are omitted from the output with the code above.
The symptom was that
-- which should work with UTF-8 encoding --
did not even get to XSLTProcessor, let alone through it.
After too much hacking I discovered the simple fix:
set substituteEntities to true in the DOMDocument for the XSL file.
That is, replace the loading of the xsl document with
<?php
$xsl = new DOMDocument;
$xsl->substituteEntities = true; // <===added line
$xsl->load('collection.xsl');
?>
If you retrieve "false" from the transformToXML method, use libxml_get_last_error() or libxml_get_errors() to retrieve the errors.
To prevent your xsl file from automatically prepending
<?xml version="1.0"?>
whilst keeping the output as xml, which is preferable for a validated strict xhtml file, rather specify output as
<xsl:output method="xml" omit-xml-declaration="yes" />
If your xsl doesn't have <html> tags. The output will contain <?xml version="1.0"?>. To fix this you can add the following to your xsl stylesheet:
<xsl:output
method="html" />
How to fix:: *Fatal error: Call to undefined method domdocument::load()*
If you get this error, visit the php.ini file and try commenting out the following, like this:
;[PHP_DOMXML]
;extension=php_domxml.dll
Suddenly, the wonderfully simple example above works as advertised.
$domTranObj = $xslProcessor->transformToDoc($domXmlObj);
$domHtmlText = $domTranObj->saveHTML();
Do fix the <meta> for valid XHTML but do not correctly end empty node like <br /> which ouput like this : <br></br>
Some browser note this as 2 different <br /> ...
To fix this use
$domTranObj = $xslProcessor->transformToDoc($domXmlObj);
$domHtmlText = $domTranObj->saveXML();
I noticed an incompatibility between libxslt (php4) and the transformation through XSLTProcessor.
Php5 and the XSLTProcessor seem to add implicit CDATA-Section-Elements.
If you have an xslt like
<script type="text/javascript">
foo('<xsl:value-of select="bar" />');
</script>
It will result in
<script type="text/javascript"><![CDATA[
foo('xpath-result-of-bar');
]]></script>
(at least for output method="xml" in order to produce strict xhtml with xslt1)
That brings up an error (at least) in Firefox 1.5 as it is no valid javascript.
It should look like that:
<script type="text/javascript">//<![CDATA[
foo('xpath-result-of-bar');
]]></script>
As the CDATA-Section is implicit, I was not able to disable the output or to put a '//' before it.
I tried everything about xsl:text disable-output-escaping="yes"
I also tried to disable implicit adding of CDATA with <output cdata-section-elements="" />
(I thought that would exclude script-tags. It didn't).
The solution:
<xsl:text disable-output-escaping="yes"><script type="text/javascript">
foo('</xsl:text><xsl:value-of select="bar" /><xsl:text disable-output-escaping="yes">');
</script></xsl:text>
Simple, but it took me a while.
The transformToXML function can produce valid XHTML output - it honours the <xsl:output> element's attributes, which defines the format of the output document.
For instance, if you want valid XHTML 1.0 Strict output, you can provide the following attribute values for the <xsl:output> element in your XSL stylesheet:
<xsl:output
method="xml"
doctype-system="http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"
doctype-public="-//W3C//DTD XHTML 1.0 Strict//EN" />
The function transformToXML has a problem with the meta content type tag. It outputs it like this:
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
which is not correct X(HT)ML, because it closes with '>' instead of with '/>'.
A way to get the output correct is to use instead of transformToXML first transformToDoc anf then saveHTML:
$domTranObj = $xslProcessor->transformToDoc($domXmlObj);
$domHtmlText = $domTranObj->saveHTML();
transformToXML, if you have registered PHP functions previously, does indeed attempt to execute these functions when it finds them in a php:function() pseudo-XSL function. It even finds static functions within classes, for instance:
<xsl:value-of select="php:function('MyClass::MyFunction', string(@attr), string(.))" disable-output-escaping="yes"/>
However, in this situation transformToXML does not try to execute "MyClass::MyFunction()". Instead, it executes "myclass:myfunction()". In PHP, since classes and functions are (I think) case-insensitive, this causes no problems.
A problem arises when you are combining these features with the __autoload() feature. So, say I have MyClass.php which contains the MyFunction definition. Generally, if I call MyClass::MyFunction, PHP will pass "MyClass" to __autoload(), and __autoload() will open up "MyClass.php".
What we have just seen, however, means that transformToXML will pass "myclass" to __autoload(), not "MyClass", with the consequence that PHP will try to open "myclass.php", which doesn't exist, instead of "MyClass.php", which does. On case-insensitive operating systems, this is not significant, but on my RedHat server, it is--PHP will give a file not found error.
The only solution I have found is to edit the __autoload() function to look for class names which are used in my XSL files, and manually change them to the correct casing.
Another solution, obviously, is to use all-lowercase class and file names.