Remove stylesheet from XML with PHP - php

Question

I'm tring to show some XML for Italian Electronic invoices received, using my custom stylesheet.xsl
All is ok when XML received start with:
<?xml version="1.0" encoding="UTF-8"?>
<p:FatturaElettronica xmlns:p="http://ivaservizi.agenziaentrate.gov.it/docs/xsd/fatture/v1.2" versione="FPR12">
but I've received some XML starting with:
<?xml version="1.0" encoding="UTF-8"?>
<?xml-stylesheet type="text/xsl" href="fatturapa_v1.2.xsl"?>
<p:FatturaElettronica xmlns:p="http://ivaservizi.agenziaentrate.gov.it/docs/xsd/fatture/v1.2" versione="FPR12">
in this case i get browser error when I try to open file because on my webapp i have not the fatturapa_v1.2.xml saved:
Error loading style sheet: XSLT style sheet interpretation failed.
Is there a way to strip out from this XML this line only, using PHP? Thanks
<?xml-stylesheet type="text/xsl" href="fatturapa_v1.2.xsl"?>

Answer 1

Everything in DOM is a node. In this case this is a processing instruction. You can use Xpath to find it and then remove it from its parent node:
$xml = <<<'XML'
<?xml version="1.0" encoding="UTF-8"?>
<?xml-stylesheet type="text/xsl" href="fatturapa_v1.2.xsl"?>
<p:FatturaElettronica xmlns:p="http://ivaservizi.agenziaentrate.gov.it/docs/xsd/fatture/v1.2" versione="FPR12"/>
XML;
$document = new DOMDocument();
$document->loadXML($xml);
$xpath = new DOMXpath($document);
foreach ($xpath->evaluate('/processing-instruction()[name() = "xml-stylesheet"]') as $pi) {
// var_dump($pi);
$pi->parentNode->removeChild($pi);
}
echo $document->saveXML();