PHP updating xml CDATA fields with DOMdocument - php

Question

I have the following XML data:
<?xml version="1.0" encoding="utf-8"?>
<source>
<publisher>some-data</publisher>
<publisherurl>some-data</publisherurl>
<lastBuildDate>a-date</lastBuildDate>
<element>
<sub-element><![CDATA[some-data]]></sub-element>
</element>
</source>
I'm trying to use PHP's built in DOMdocument parser to update the text inside sub-element.
I've tried:
$dom=new DOMDocument();
$dom->load("document.xml");
$ele=$root->getElementsByTagName('element');
foreach ($ele as $e) {
$e->getElementsByTagName('sub-element')->item(0)->nodeValue = "new val";
}
this kind of works but it removes the CDATA and just replaces it with new-val. I want to preserve the CDATA field so I tried the following:
$dom=new DOMDocument();
$dom->load("document.xml");
$ele=$root->getElementsByTagName('element');
foreach ($ele as $e) {
$sub=$e->getElementsByTagName('sub-element');
foreach($sub->childNodes as $child) {
if ($child->nodeType == XML_CDATA_SECTION_NODE) {
$child->nodeValue = 'new-val';
}
}
}
This seems like it should work but PHP returns the following Notice
Undefined property: DOMNodeList::$childNodes
Feel like I'm on the right path but I just can't figure out what I'm doing wrong here. Does anyone know how to fix?
My end goal output is:
<?xml version="1.0" encoding="utf-8"?>
<source>
<publisher>some-data</publisher>
<publisherurl>some-data</publisherurl>
<lastBuildDate>a-date</lastBuildDate>
<element>
<sub-element><![CDATA[new-val]]></sub-element>
</element>
</source>

Answer 1

You need to compare against firstChild
$xml = '<?xml version="1.0" encoding="utf-8"?>
<source>
<publisher>some-data</publisher>
<publisherurl>some-data</publisherurl>
<lastBuildDate>a-date</lastBuildDate>
<element>
<sub-element><![CDATA[some-data]]></sub-element>
</element>
<element>
<sub-element>some-other-data</sub-element>
</element>
</source>';
$dom = new DOMDocument();
$dom->loadXML($xml);
$ele=$dom->getElementsByTagName('element');
foreach ($ele as $e) {
$item = $e->getElementsByTagName('sub-element')->item(0);
if($item->firstChild->nodeType == XML_CDATA_SECTION_NODE) { //<------
//it's CDATA do whatever
$item->firstChild->nodeValue = "new val";
} else {
//it's not , do something else
$item->nodeValue = "new val";
}
}
echo "<pre>";
print_r(htmlentities($dom->saveXML()));
echo "</pre>";
Output:
<?xml version="1.0" encoding="utf-8"?>
<source>
<publisher>some-data</publisher>
<publisherurl>some-data</publisherurl>
<lastBuildDate>a-date</lastBuildDate>
<element>
<sub-element><![CDATA[new val]]></sub-element>
</element>
<element>
<sub-element>new val</sub-element>
</element>
</source>
PS: if you don't have to make a distinction between CDATA or not, just use firstChild
foreach ($ele as $e) {
$item = $e->getElementsByTagName('sub-element')->item(0);
$item->firstChild->nodeValue = "new val";
}