PHP Manual: DOMDocument::append

public function DOMDocument::append(DOMNode|string ...$nodes): void

Appends one or many nodes to the list of children after the last child node.

nodes: The nodes to append. Strings are automatically converted to text nodes.

No value is returned.

DOM_HIERARCHY_REQUEST_ERR: Raised if this node is of a type that does not allow children of the type of one of the passed nodes, or if the node to put in is one of this node's ancestors or this node itself.
DOM_WRONG_DOCUMENT_ERR: Raised if one of the passed nodes was created from a different document than the one that created this node.

Version	Description
8.3.0	Calling this method on a node without an owner document now works. Previously this threw a DOMException with code `DOM_HIERARCHY_REQUEST_ERR`.

Example #1 DOMDocument::append() example

Adds nodes after the document root.

<?php
$doc = new DOMDocument;
$doc->loadXML("<hello/>");

$doc->append("beautiful", $doc->createElement("world"));

echo $doc->saveXML();
?>

The above example will output:

<?xml version="1.0"?>
<hello/>
beautiful
<world/>

DOMDocument::append