learn php for xml file editing

I have example to edit attribute, need examples to add, move node with attributes. Worked logic in file "[login to view URL]": $xml = simplexml_load_file($fname); $n = $xml->xpath($xpath); $n[0][$sattr] = $snew; $xml->asXML($fname); By the same logic, i need php files: [login to view URL] [login to view URL] [login to view URL] php example included xml files for test included txt files for readme included