XSD unordered sequence with undefined elements ignored

[klikic]

Hi.
How can create a unordered sequence with defined elements that can
occur ones and "other" elements that are ignored.
Example:
XML:
<Recur>
<ignoredElement>saasda</ignoredElement>
<frequency>sdsad</frequency>
<recurEnd>kjdskdj</recurEnd>
</Recur>

Elements "frequency" and "recurEnd" are not optional and can occur only
ones. Element "ignoredElement" or any other element taht is not
defined, can occur multiple times or none, and can be at any position
(between mandatory elements or at end,...).

I created XSD:
<xs:element name="Recur">
<xs:complexType mixed="false">
<xs:sequence maxOccurs="unbounded">
<xs:element ref="frequency"/>
<xs:element ref="endRecur"/>
<xs:any namespace="##other" minOccurs="0" maxOccurs="unbounded"//>
</xs:sequence>
</xs:complexType>
</xs:element>

This doesn't work: I have errors while validating XML with XSD.
I tried with choice but with same effect.
Any help or suggestion would be nice.
Thanks.
Alan

 

[klikic]

I am sorry I made a mistake:
element in XML is not recurEnd but endRecur.

 

[George Bina]

Hi,

You cannot do that with XML Schema. All you can do is to relax the
content model allowing more than what you want, use <xs:choice
maxOccurs="unbounded">. If Relax NG does not scare you then look into
that. Alternatively you can add a couple of Schematron rules inside XML
Schema to enforce one occurrence of frequency and endRecur elements.
See below a complete example that uses Schematron embedded rules:

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
targetNamespace="http://www.example.com"
xmlns:t="http://www.example.com">
<xs:annotation>
<xs:appinfo>
<ns xmlns="http://www.ascc.net/xml/schematron"
uri="http://www.example.com" prefix="t"/>
</xs:appinfo>
</xs:annotation>
<xs:element name="Recur">
<xs:annotation>
<xs:appinfo>
<pattern xmlns="http://www.ascc.net/xml/schematron"
name="test">
<rule context="t:Recur">
<assert test="count(t:frequency)=1">There should be one
occurrence of frequency.</assert>
<assert test="count(t:endRecur)=1">There should be one
occurrence of endRecur.</assert>
</rule>
</pattern>
</xs:appinfo>
</xs:annotation>
<xs:complexType mixed="false">
<xs:choice maxOccurs="unbounded">
<xs:element name="frequency" form="qualified"
type="xs:string"/>
<xs:element name="endRecur" form="qualified"/>
<xs:any namespace="##other" minOccurs="0" maxOccurs="unbounded"
processContents="lax"/>
</xs:choice>
</xs:complexType>
</xs:element>
</xs:schema>

Best Regards,
George