Question about tag and value

[mittra]

Hello All,

I am a newbie to XML. I have the following question: how do I express
something in XML when the subsequent tag structures depends on the
value of a preceeding tag?

For example, when TAG2 has a value of 1, then TAG3 exists.

<TAG1>
<TAG2>1</TAG2>
<TAG3>some_value</TAG3>
</TAG1>

But when TAG2 has a value of 2, then TAG4 exists.

<TAG1>
<TAG2>2</TAG2>
<TAG4>some_value2</TAG4>
</TAG1>

Can the above two be combined into a single structure for TAG1?

Thanks for your insight.

[Philippe Poulard]

hi,

mi****@juno.com a écrit :

>
if (TAG2 value is 1) then
<TAG3>some_value</TAG3>
else
<TAG4>some_value2</TAG4>

Perhaps, XML Schema does it?

this is exactly the way the Active Schema Language works : you can
define dynamically the content model that suits your needs, potentially
with the help of if-then-else statements

although ASL is experimental, it is implemented and works fine : you can
use it for your own needs if you don't have to share your own schemas
with third-party users ; ASL will allow you to express much more complex
constraints than legacy schema technologies can (DTD, W3C XML Schema,
RelaxNG, Schematron)

the implementation :
http://reflex.gforge.inria.fr/
the specification :
http://ns.inria.fr/active-tags/activ...ve-schema.html
some tutorials :
http://reflex.gforge.inria.fr/tutorial-schemas.html

if you are new to XML, you'll have to understand namespaces in XML and
learn XPath before (which are widely used in XML technologies)

some courses :
http://disc.inria.fr/perso/philippe....namespaces.pdf
http://disc.inria.fr/perso/philippe....-xml-xpath.pdf
....if you are new to french, you'll have to learn french before :)

--
Cordialement,

///
(. .)
--------ooO--(_)--Ooo--------
| Philippe Poulard |
-----------------------------
http://reflex.gforge.inria.fr/
Have the RefleX !