SimpleXML get node value

A good example of using XPath with php for the SimpleXMLElement can be found here http://www.php.net/manual/en/class.simplexmlelement.php#95229

// Find the topmost element of the domDocument
$xpath = new DOMXPath($xml);
$child1 = $xpath->evaluate('/main/parent/child1')->item(0); 

$xml = new SimpleXMLElement($xml);
$this->xmlcode = (string) $xml->parent[0]->child1;