PHP simpleXML example

index.php

<?php

	//first grab the xml file
	$xml=simplexml_load_file("http://www.stateair.net/web/rss/1/1.xml");

	/* simpleXML let's you parse through the entire file */
	/* info: http://www.w3schools.com/php/php_xml_simplexml.asp */
	//foreach($xml->children() as $child) {
	//	echo $child->getName() . ": " . $child . "<br>";
	//}

	/*this line will print out the value by itself to the browser: */
	//echo "current AQI value: " . $xml->channel[0]->item[0]->AQI;

	/* we let the arduino know that a message has arrived by starting
	the value with a '#' and ending it with a '!'. So, whatever we want 
	the arduino to receive, we wrap with those characters. */

	//test setup:
	$testValue = 15; //test variable
	echo "#" . $testValue . "!"; //echo out the test variable

 	//this is returning the FIRST ITEM'S AQI (uncomment)
	//echo "#" . $xml->channel[0]->item[0]->AQI . "!";
 	
 ?>