Selecting parent nodes with XMLReader

Question

I had to rewrite part of a programme to use XMLReader to select parts of an XML file for processing.

Take this simplified XML as an example:

Answer 1

[Ignore the SimpleXML solution and look down at the XMLReader one]

I would suggest using the SimpleXMLElement::xpath method.

http://php.net/manual/en/simplexmlelement.xpath.php

$xml = new SimpleXMLElement($xml_string);

/* Search for  */
$result = $xml->xpath("/odds/sport/region/group/event/bet");

$result will contain all children of 'bet' note.

// XMLReader solution **********************

$reader = new XMLReader;
$reader->open('file.xml');
$parent_element = null;

while($reader->read()) {
    $selectionid = $reader->getAttribute('selectionid'); 

    if ($selectionid == '52411062.1' ) {
        // use the parent of the node with attribute 'selectionid' = '52411062.1'
        $node = $parent_element;
        var_dump($node);
        break;
    }
    elseif ($reader->name === 'bet') { )
    {
        // store parent element
        $parent_element = new SimpleXMLElement($reader->readOuterXML());
    }
}