How to Efficiently Retrieve DOM Elements by Class Name in PHP?

Retrieving DOM Elements Based on Class Name

In PHP DOM, extracting elements with specific class names is essential. This question presents a challenge faced by developers: finding the optimal method to isolate such elements within a DOM node.

To address this issue, several approaches are presented:

• XPath Selector: A concise solution is to employ XPath syntax. Consider the following example:

$dom = new DomDocument();
$dom->load($filePath);
$finder = new DomXPath($dom);
$classname = "my-class";
$nodes = $finder->query("//*[contains(@class, '$classname')]");

• CSS Selector with Zend_Dom_Query: For more complex scenarios, leveraging Zend_Dom_Query is recommended. Its CSS selector support enables convenient element retrieval:

$finder = new Zend_Dom_Query($html);
$classname = 'my-class';
$nodes = $finder->query("*[class~=\"$classname\"]");

Additionally, for scenarios involving XPath selectors with class name criteria, a more refined version is available:

$classname = "my-class";
$nodes = $finder->query("//*[contains(concat(' ', normalize-space(@class), ' '), ' $classname ')]");

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