This week wraps up a look at "XML and PHP" with a few examples demonstrating how WDDX makes it possible to exchange data between different sites and systems in a simple and elegant manner. From New Riders.
Vikram Vaswani demonstrates how WDDX can be combined with PHP to encode and exchange data across different systems and platforms. Book excerpt from New Riders.
SOAP is an XML-based protocol that lets you activate an application,
or even an individual object or method within an application, across
the Internet. SOAP could revolutionize the whole process of
developing Web applications.
Chapter 13 of Beginning XHTML, from Wrox
Press covers different media types and why they are necessary. Main
subjects include the role of Cascading Style Sheets in supporting media
types, the differences between media types and how to handle them and
the future of style sheets in XML.
The Extensible Markup Language allows you to create
custom languages (technically called vocabularies) for
particular applications, which can be anything from a Web
page to an e-commerce interface to a game to a complete
virtual world. Here's an overview of how (and why) to create
your own custom XML vocabularies, as well as examples of
some existing ones.
Update: XHTML 1.0 was released on January 26th as a
Recommendation by the W3C. XHTML 1.0 is the first step toward a
modular and extensible web based on XML (Extensible Markup
Language). It provides the bridge for web designers to enter the web
of the future, while still being able to maintain compatibility with
today's HTML 4 browsers.
Offsite XML-Related Tutorials
by Various Authors
We've collected the best free XML-related tutorials from non-WDVL authors below.
If you have other favorites, contact Ken Sall.
W3Schools (formerly XML School):
tutorials in HTML, CSS, DHTML, XHTML, WML, XML, XSL, DTD, DOM, WAP, SOAP,
XSchema, XForms and more.
Somewhat Microsoft focused. Sister site is
XML101.com.
SVG is positioned to have a major impact on Web graphics
because it enables resolution independent graphic rendering
either from static text files or when generated from databases,
and because it leverages many of the useful features of the XML
family of specifications.
Is HTML 4.0 the end of the road? Will all future changes be in terms
of XML? Will there be an HTML Classic? See what the W3C has to say
on their HTML
Activity page and in a members-only workshop entitled
Shaping the Future of HTML
(May 1998).
Why are so many Java programmers interested in XML?
What Java APIs exist to interface to XML?
What tools written in Java are already available?
Read WDVL's 3-part article to find out. See
XML and Java: The Perfect Pair.
In this XML tutorial, Ken Sall turns to some of the practical
considerations facing Web developers of every level.
How can you get started with XML now?
How can you go from an XML document instance to a DTD?
How can you view the results?
How can Internet Explorer 5 and other free or inexpensive tools help?
How can you edit the XML in a way that guarantees it will match the DTD?
How can you use CSS
or XSL
to control both the presentation and processing of your XML?
This month we focus on several inexpensive tools
for editing XML: XML Pro,
XML Spy, Xeena, and XML EditorMaker. How to use
CSS (cascading Style
Sheets) or
XSL
(Extensible Stylesheet Language) to control both the
presentation and processing of your XML (especially in IE 5)
is also covered. A
more complete WDVL treatment of XSL will follow later this
summer and fall
when the
XSL Working Draft
becomes a full
W3C Recommendation
This WDVL article focuses on the way in which the various
specifications fit into the Big Picture of the efforts of the
World Wide Web Consortium (W3C).
Next Generation HTML encompasses
Cascading Style Sheets,
HTML 4.0, the
Document Object Model,
Dynamic HTML, the
XML family
of specifications, and the many specifications based on
XML, such as
RDF, SMIL,
and MathML. When we read about a W3C specification, it is useful
to understand its role in the larger picture. To help you visualize
the Big Picture, we introduce a
graphic which doubles as an
imagemap to whisk you directly to pages containing details about
each topic. A color coding key in the imagemap informs you of the
current status of each W3C document. We've also included an
acronym
expansion chart because the buzz words are far too many to remember.
Regardless of its mild-mannered appearance, XML is one of the most
exciting and potentially powerful internet standards/technologies to
be released in quite some time. XML allows web developers to abstract
data sets from data formatting and data description in a way that
makes applications much more easy to program, and data sets far more
portable.
In this tutorial, Selena Sol walks you through XML and the sister XSL
style sheet language. Using simple, well-explained examples, Sol
shows you how to get up to speed with the syntax of XML as well as
helps you develop the more intuitive skill of learning how and when to
apply XML to a problem.
As was discussed in part one, XML allows you to generate an infinite
number of custom tags sets for your documents. However, though you are
free to be as innovative as you want with the XML tag sets that you
create, you must follow the constraints of the XML tag set generation
standards exactly. In other words, your XML documents must be
"well-formed". Well-formedness has an exact meaning in XML. Specifically,
a well-formed document adheres to the syntax rules specified by the XML
1.0 specification. In this month's tutorial, Selena will look at those
rules in depth.
As you have seen in the previous sections of this tutorial,
there are many rules you must
follow in order to assure that your XML document
is well-formed. But even when you
write well-formed XML documents, you're not quite out
of the woods! Making your
document well-formed is only half the battle. You must also
make sure that the document
is valid. This third and final section deals with making your
well-formed XML document
valid by using a DTD.
While XML is a powerful, flexible, and intuitive way to
structure data, it does not, by itself, process the data as such. One
technology which can be employed to process XML data is the Document
Object Model, a construct which provides programmatic access to the
components of an XML document.
The Synchronized Multimedia Integration Language is a
recommendation from the W3C that
allows for the creation of time-based multimedia delivery over the
web. Based on XML, it allows developers to mix many types of
media, text, video, graphics, audio and vector based animation
together and to synchronize them to a timeline.
RealPix is the graphics format developed by Real Networks. It
allows graphics to be streamed over web as part of Synchronized
Multimedia Integration Language (SMIL). RealPix is one of the
many media types that can be played back in the G2 Player from
RealNetworks.
RealAudio is the classic streaming audio solution developed by Real
Networks. In its latest incarnation, it not only allows audio to be
streamed over web, it is part of Synchronized Multimedia Integration
Language (SMIL) and synchronized with other Real media types in
the G2 Player from RealNetworks.
You may also be interested in our
XML Training page.
Submit additions or corrections to Ken Sall
for consideration.
