Basically what I'm trying to achieve is replacing the content of the src-attributes of a bunch of img-nodes by the content of the corresponding data-src-nodes in a page like the following one.
<html>
<body>
<div id="a">
<img src="" data-src="myValue" />
<img src="" data-src="myValue2" />
</div>
<img src="" data-src="myValue" />
</body>
</html>
I want to do this by finding a common base node (in this case the img nodes in the div with id a) and based on that node
- the node containing the value to copy and#
- the node retrieving the value
Script
<?PHP
$html = '<html><body><div id="a"><img src="" data-src="myValue"/><img src="" data-src="myValue2"/></div><img src="" data-src="myValue"/></body></html>';
$doc = new DOMDocument();
@$doc->loadHTML($html);
$basenode = false;
$xpath = new DOMXPath($doc);
$entries = $xpath->query('(//div[@id="a"])');
if ($entries->length > 0) $basenode = $entries->item(0);
if ($basenode) {
$img = $xpath->query('//img', $basenode);
foreach ($img as $curImg) {
$from = $xpath->query('//@data-src', $curImg);
$to = $xpath->query('//@src', $curImg);
$to->item(0)->value = $from->item(0)->value;
}
echo $doc->saveXML();
}
?>
Expected output
<html>
<body>
<div id="a">
<img src="myValue" data-src="myValue" />
<img src="myValue2" data-src="myValue2" />
</div>
<img src="" data-src="myValue" />
</body>
</html>
Actual output
<html>
<body>
<div id="a">
<img src="myValue" data-src="myValue" />
<img src="" data-src="myValue2" />
</div>
<img src="" data-src="myValue" />
</body>
</html>
So, the line
$from = $xpath->query('//@data-src', $curImg);
seems to actually base its search on the root node and not the img-node selected before. How can I solve this?
(I know that a possible workaround would be to omit selecting the img-nodes explicitly and doing something like from='//div[@id="a"]/img/@data-src' and to='//div[@id="a"]/img/@src' but I'm a bit concerned, that I might end up copying values between attributes of different nodes)
