How to read XML file in PHP

<?php
$str = <<<XML
<currencies>
    <currency name="US dollar" code_alpha="USD" code_numeric="840" />
    <currency name="Euro" code_alpha="EUR" code_numeric="978" />
</currencies>
XML;

$dom = new DOMDocument();
$dom->loadXML($str);

foreach($dom->getElementsByTagName('currency') as $currency)
{
    echo $currency->getAttribute('name'), "\n";
    echo $currency->getAttribute('code_alpha'), "\n";
    echo $currency->getAttribute('code_numeric'), "\n";
    echo "+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+\n";
}
?>