- simplexml_load_string: documentation ( source)
<?php
$x = <<<XML
<MembershipCardLists><MembershipCardInfo>
<CardNo>8898990000000083</CardNo>
</MembershipCardInfo>
<MembershipCardInfo>
<CardNo>8898000000000260</CardNo>
</MembershipCardInfo></MembershipCardLists>
XML;
$xml = simplexml_load_string($x);
$i = 0;
foreach ($xml->MembershipCardInfo as $card):
$cardArray[$i] = $card->CardNo;
$i++;
endforeach;
foreach ($cardArray as $item) {
echo $item.'<br />';
}