AJAX - The Complete Reference

Chapter 4: Data Formats 153

PART I

<votes id=\"votes\">$votes</votes>

</pollresults>";

echo $message;

While this is the most direct method to create an XML response, you might instead

employ DOM features of your server-side framework instead, as demonstrated here:

header("Cache-Control: no-cache");

header("Pragma: no-cache");

header("Content-Type: text/xml");

$xml = new DOMDocument('1.0', 'UTF-8');

$root = $xml->createElement("pollresults");

$ratingNode = $xml->createElement("rating");

$ratingNode->appendChild($xml->createTextNode($rating));

$ratingNode->setAttribute("id", "rating");

$root->appendChild($ratingNode);

$averageNode = $xml->createElement("average");

$averageNode->appendChild($xml->createTextNode($average));

$averageNode->setAttribute("id", "average");

$root->appendChild($averageNode);

$votesNode = $xml->createElement("votes");

$votesNode->appendChild($xml->createTextNode($votes));

$votesNode->setAttribute("id", "votes");

$root->appendChild($votesNode);

$xml->appendChild($root);

$message = $xml->saveXML();

echo $message;

Depending on your application architecture, you may even have XML packets formed

directly by printing the results of queries to your back-end datastore. This is a bit beyond

what we are talking about here, and regardless of how the XML is created, it will look the

same across the wire: