What are the best practices for integrating XML validation using XSD in PHP?

When integrating XML validation using XSD in PHP, it is best practice to use the `DOMDocument` class to load the XML file and validate it against the XSD schema using the `schemaValidate` method. This ensures that the XML document adheres to the specified structure defined in the XSD schema.

// Load the XML file
$xml = new DOMDocument();
$xml->load('example.xml');

// Load the XSD schema
$xsd = new DOMDocument();
$xsd->load('schema.xsd');

// Validate the XML against the XSD schema
if ($xml->schemaValidate($xsd)) {
    echo 'XML is valid.';
} else {
    echo 'XML is invalid.';
}