用PHP替换图像标签周围的链接

Question

I have a string (in Wordpress) with HTML content and I want to replace every link URL around an image tag with another URL:

Before: <a href="A"><img src="X"></a>
After: <a href="B"><img src="X"></a>

First I wanted to do it with regular expressions, but then I read that this not recommended at all. So is there a possibility to do this with PHP?

Answer 1

Use the DOM API

$doc = new DOMDocument();
$doc->loadHTML($htmlString, LIBXML_HTML_NOIMPLIED | LIBXML_HTML_NODEFDTD);
// the flags are for if you're not using a complete document, ie an HTML fragment
// You'll need the libxml extension enabled

$xpath = new DOMXPath($doc);

// find all <a> tags with an "href" attribute and <img> child element
$links = $xpath->query('//a[@href and img]');
foreach ($links as $link) {
    $link->setAttribute('href', 'B');
}
$newHtmlString = $doc->saveHTML();

Demo ~ https://3v4l.org/ZHTYG

Answer 2

Yes, you can do it easily with DOMDocument :

$dom = new DOMDocument();
$dom->loadHTML('<a href="A"><img src="X"></a>');

foreach ($dom->getElementsByTagName('a') as $item) {
    $item->setAttribute('href', 'B');
    echo $dom->saveHTML();
}