Re: Netscape 6 support for XML

Jack wrote:


> This does make me doubt the extent to which XHTML
> served as XML is suopported by older browsers. According to W3C, one of the
> main advantages of  XHTML over HTML is that it allows you to define your own
> entities. If external DTDs are not loaded by some User Agents, then it is
> obviously going to be more difficult to do this.

Let's face it, XHTML 1.0 semantically has nothing to offer compared to 
HTML 4.01, HTML 4.01 is a SGML application and XHTML 1.0 is a 
reformulation as an XML application so on the web in general as long as 
you are looking for the functionality of HTML 4.01 use it and not it 
XHTML 1.0, with HTML 4.01 and text/html you get much better support in 
the user agents.
XML and then XHTML as a consequence have been introduced to reduce the 
complexity of SGML and SGML parsers, where on the web in a browser the 
HTML parsers were and are not simply strict SGML parsers but "tag soup" 
parsers trying to deal with any markup thrown at them and to "correct" 
and interpret it in a way to render it. X(HT)ML does no longer require 
that, if some XHTML is not well-formed XML then the page doesn't have to 
be rendered, it suffices to show a parse error message. Thus if someone 
only has to build an XHTML renderer he can use an XML parser or build 
one and end up with much slimmer software compared to existing browsers. 
Only existing browsers can not give up on text/html HTML tag soup 
parsing but have to offer both worlds currently and while Opera and 
Mozilla have put effort in XML and XHTML support it has certainly taken 
time and releases to get it going. So you are right, XHTML as XML with 
older browsers (or perhaps older releases of the newly designed and 
created browsers such as Netscape 6 or early Opera 7) is certainly not 
something to rely on.
Still, as said above, XHTML 1.0 doesn't help you, where XHTML makes 
sense in my view is when it comes to mixing XHTML with other languages 
in different namespaces, for instance Mozilla has XHTML plus MathML 
support and that is certainly something worth looking at XML and XHTML. 
(But don't bother with trying that with Netscape 6, you need at least 
Mozilla 1.4 or Netscape 7.1 then).


> I tried entering the acute-accented vowels using Notepad. Unfortunately
> these are displayed as question marks in Netscape 6.2 (but if you use IE6 to
> look at the source you cansee the accented vowels). See
> http://homepage.ntlworld.com/r.a.mccartney/test/test_file_for_utf-8_accents_without_entities.xml

I have loaded that page with Netscape 7.2, Opera 7.50 and IE 6 and I 
think there is no fault with the two browsers named first not rendering 
accents, the XML declaration says it is UTF-8 but I don't think it is. 
Indeed trying to parse the page with MSXML 4, Microsoft's XML parser, 
gives an error
   "An invalid character was found in text content."
for line 15.

So you need to make sure you are really creating your page as UTF-8, 
then I am sure Mozilla 1.0 and later (or Netscape 7.0 and later) can 
handle accented characters. No promise about Netscape 6, it is too long 
ago to remember details about its XML and UTF-8 support and I don't have 
it to test here, but I would be suprised if a simple XML page properly 
encoded and declared as UTF-8 would cause problems.



-- 

	Martin Honnen
	http://JavaScript.FAQTs.com/