XHTML and scripting

[Kennis]

I'm just getting to grips with XHTML standards at the moment. It's fairly straightforward making basic HTML compliant to XHTML but what are the specifications/rules for making sure that all scripts (javascript, DHTML, etc.) are compliant to XHTML? Is scripting handled differently or even accounted for?

[Zvona]

Not really. XHTML is used for defining structure of a document, which won't directly affect on scripting. I've noticed minor style differences with CSS between HTML 4.01 DTD and XHTML 1.0 DTD.

[jkd]

One thing to be careful about:

<script type="text/javascript">
if (something < bla) {
// ....
}
</script>

Suddenly your document becomes invalid. Because Javascript extensively uses the <, >, and & signs, you either need to replace all occurrences of them with:
&amp;lt; --> "<"
&amp;gt; --> ">"
&amp;amp; --> "&"

But since that will definitely cause issues with browsers not truely supporting XHTML, you put the entire script in a <![CDATA script contents ]]> section. Once again though you run into older browser support, which is finally solved by a little hack:

<script type="text/javascript">
<!--// <![CDATA
//script contents
// ]]> -->
</script>


Also, if you dynamically generate any content, be sure you generate valid markup. (Using W3C DOM methods automatically takes care of it for you, but be wary with innerHTML and the such.)

[Alex Vincent]

Or you could always outsource your scripts...

<script language="JavaScript" type="text/javascript" src="myscript.js"></script>

That seems to be the easiest of all.

[jkd]

Originally posted by Alex Vincent
Or you could always outsource your scripts...

<script language="JavaScript" type="text/javascript" src="myscript.js"></script>

That seems to be the easiest of all.

True, but can be inconvenient at times.