Flex 3 Cookbook

Chapter 19. XML

Flex 3 and ActionScript 3.0 provide ECMAScript for XML, or E4X, implementation that enables you to work with dot notation to access the nodes within an XML hierarchy. E4X provides a simplified shorthand notation so you can access specific nodes or sets of nodes by name or by index without complicated custom recursive functions. It also defines methods and properties for accessing all parts of the XML object, including comments, namespaces, and processing instructions. The Flex Framework and ActionScript 3.0 define two low-level objects for working with XML: the XML object and the XMLList object. The XML object represents a single XML element, an XML document with multiple children, or a single-value element within a document. The XMLList object represents a set of XML elements that are siblings of one another. XMLList objects do not require a top-level node, for example:

<item id="2" name="Chewing Gum"/>
<item id="3" name="Cotton Candy"/>
<item id="4" name="Candy Bar"/>

XML objects do require a top-level node:

<order>
    <item id="2" name="Chewing Gum"/>
    <item id="3" name="Cotton Candy"/>
    <item id="4" name="Candy Bar"/>

</order>

To perform XML transformations or to build XML documents, both the XML and XMLList objects define methods to append, rename, and re-parent nodes within an XML document. To perform queries, access particular attributes, or filter XML documents, use the E4X querying syntax. For working with XML namespaces, the XMLUtil class defines methods of accessing ...