Change element in XML file

[Packy]

Simple problem, hope simple solution.

 

How to edit element in XML file?

 

Here what I have been trying...

 

<?php

$dom = new DOMDocument;

$dom->load('XML/sample.xml');

 

if ($dom->getElementsByTagname('Static_IP')) {

$Static_IP = $dom->getElementsByTagname('Static_IP');

$Static_IP_value = $Static_IP->item(0)->firstChild->nodeValue;

 

print "IP address: $Static_IP_value";

 

$IPaddress =10.10.1.1;

 

????????????

How to add this variable into te element name Static_IP

????????????

 

 

$dom->formatOutput = true;

$sample = $dom->saveXML();

$dom->save('XML/sample.xml');

 

?>