Conditional Expressions in XML Schema?

Hi,

    Today we were trying to figure out a way to do some conditional
constraints using XML schema.  We did not really find a good way. Maybe
you know of

One. If there isn't one in the specification, maybe it would be a good
candidate for an enhancement.  What we were trying to do is the
following:

 

  Basically define element A with a set of restricted values.

  Then, based on the value of A, restrict the values of element B.

 

  For example, if A was set to NO,  B could only be set to HTTP. Rich,
or Plain.

  If A was set to YES,  B could only be set to XML.

 

Is there a way today to define this kind of conditional constraint in
XML?

 

Thanks,

Tom

 

Thomas J. Czernik

Software Engineer

732-935-0095 x121

www.future-skies.com <http://www.future-skies.com/>