ADOBE® FLEX® 3: PROGRAMMING ACTIONSCRIPT™ 3.0

ADOBE FLEX 3

Developer Guide

221

Using the for..in and the for each..in statements

ActionScript 3.0 includes the for..in statement and the for each..in statement for iterating through XMLList

objects. For example, consider the following XML object,

myXML, and the XMLList object, myXML.item. The

XMLList object,

myXML.item, consists of the two item nodes of the XML object.

var myXML:XML =

<order>

<item id='1' quantity='2'>

<menuName>burger</menuName>

<price>3.95</price>

</item>

<item id='2' quantity='2'>

<menuName>fries</menuName>

<price>1.45</price>

</item>

</order>;

The for..in statement lets you iterate over a set of property names in an XMLList:

var total:Number = 0;

for (var pname:String in myXML.item)

{

total += myXML.item.@quantity[pname] * myXML.item.price[pname];

}

The for each..in statement lets you iterate through the properties in the XMLList:

var total2:Number = 0;

for each (var prop:XML in myXML.item)

{

total2 += prop.@quantity * prop.price;

}

Using XML namespaces

Namespaces in an XML object (or document) identify the type of data that the object contains. For example, in

sending and delivering XML data to a web service that uses the SOAP messaging protocol, you declare the

namespace in the opening tag of the XML:

var message:XML =

<soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/"

soap:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/">

<soap:Body xmlns:w="http://www.test.com/weather/">

<w:getWeatherResponse>

<w:tempurature >78</w:tempurature>

</w:getWeatherResponse>

</soap:Body>

</soap:Envelope>;

The namespace has a prefix, soap, and a URI that defines the namespace,

http://schemas.xmlsoap.org/soap/envelope/.

ActionScript 3.0 includes the Namespace class for working with XML namespaces. For the XML object in the

previous example, you can use the Namespace class as follows: