A Philosophical Interlude
Before proceeding to the last example of dynamic text, there's
an issue that we need to address. Those of you who have been
Internet ExplorerTM®© to do dynamic HTML
are probably asking:
Why do I need to go to all this trouble with nodes
and children? All I need to do in Internet Explorer is
modify the innerText or innerHTML property
to get the same effect.
Two reasons, and these are personal opinions, by the way, so
take them for what they're worth.
The innerText and innerHTML properties
are Microsoft only and non-standard. I prefer to stick with
standards that are agreed upon by the
World Wide Web Consortium, because
I know they'll work in any browser, on any platform, that conforms
to those standards. This will become important in the future, when
PDAs (Personal Digital Assistants) and web tablets
start to become popular. The smaller ones may not have the
memory capacity or speed to handle all the varieties of non-standard
extensions that have been made to HTML; the trend appears to be
that these devices will be standards-compliant.
The very name innerHTML implies that it is
tied to HTML. The Document Object Model, however, is generic.
It applies not only to HTML documents, but also to XML documents.
The knowledge acquired in maniuplating the DOM with HTML will be
immediately transferable to this new up-and-coming technology.
End of sermon. Now, on to an example that shows the power of
being able to use the DOM to dynamically modify a document.