Question

is there a way to retrieve only the immediate children found by a call to DOMElement::getElementsByTagName? For example, I have an XML document that has a category element. That category element has sub category elements (which have the same structure), like:

<category>
    <id>1</id>
    <name>Top Level Category Name</name>
    <subCategory>
        <id>2</id>
        <name>Sub Category Name</name>
    </subCategory>
    ...
</category>

If I have a DOMElement representing the top level category,

$topLevelCategoryElement->getElementsByTagName('id');

will return a list with the nodes for all ‘id’ elements, where I want just the one from the top level. Any way to do this outside of using XPath?

Answer 1

I’m afraid not. You’ll have to iterate through the children or use XPath.

for ($n = $parent->firstChild; $n !== null; $n = $n->nextSibling) {
    if ($n instanceof DOMElement && $n->tagName == "xxx") {
        //...
    }
}

Example with XPath and your XML file:

$xml = ...;
$d = new DOMDocument();
$d->loadXML($xml);
$cat = $d->getElementsByTagName("subCategory")->item(0);
$xp = new DOMXpath($d);
$q = $xp->query("id", $cat); //note the second argument
echo $q->item(0)->textContent;

gives 2.