In this example, each parent <book> tag
contains three child tags: <pubdate>, <title>,
and <author>. But each <book> tag
is also a child tag of the <mybooks> tag,
which is one level higher in the schema. You can name and structure
XML tags in any way, provided that you nest tags accordingly within others,
and assign each opening tag a corresponding closing tag.
do not contain any formatting—they are simply containers of structured
information. Once you have an XML schema, you can use the Extensible
Stylesheet Language (XSL) to display the information. In the way
that Cascading Style Sheets (CSS) let you
format HTML, XSL lets you format XML data. You can define styles,
page elements, layout, and so forth in an XSL file and attach it
to an XML file so that when a user views the XML data in a browser,
the data is formatted according to whatever you’ve defined in the
XSL file. The content (the XML data) and presentation (defined by
the XSL file) are entirely separate, providing you with greater
control over how your information appears on a web page. In essence,
XSL is a presentation technology for XML, where the primary output
is an HTML page.
Stylesheet Language Transformations (XSLT) is a subset language
of XSL that actually lets you display XML data on a web page, and
“transform” it, along with XSL styles, into readable, styled information
in the form of HTML. You can use Dreamweaver to
create XSLT pages that let you perform XSL transformations using
an application server or a browser. In a server-side XSL transformation,
the server does the work of transforming the XML and XSL, and displaying
it on the page. In a client-side transformation, a browser (such
as Internet Explorer) does the work.
The approach you ultimately take (server-side transformations
versus client-side transformations) depends on what you are trying
to achieve as an end result, the technologies available to you,
the level of access you have to XML source files, and other factors.
Both approaches have their own benefits and limitations. For example,
server-side transformations work in all browsers while client-side
transformations are restricted to modern browsers only (Internet
Explorer 6, Netscape 8, Mozilla 1.8, and Firefox 1.0.2). Server-side
transformations let you display XML data dynamically from your own
server or from anywhere else on the web, while client-side transformations
must use XML data that is locally hosted on your own web server.
Finally, server-side transformations require that you deploy your pages
to a configured application server, while client-side transformations
only require access to a web server.
For a tutorial about understanding XML, see www.adobe.com/go/vid0165.