XSD: xs:sequence & xs:choice combination for xs:extension elements of a common base type?
- by bguiz
Hi,
My question is about defining an XML schema that will validate the following XML:
<rules>
<other>...</other>
<bool>...</bool>
<other>...</other>
<string>...</string>
<other>...</other>
</rules>
The order of the child nodes does not matter. The cardinality of the child nodes is 0..unbounded.
All the child elements of the rules node have a common base type, rule, like so:
<xs:complexType name="booleanRule">
<xs:complexContent>
<xs:extension base="rule">
...
</xs:extension>
</xs:complexContent>
</xs:complexType>
<xs:complexType name="stringFilterRule">
<xs:complexContent>
<xs:extension base="filterRule">
...
</xs:extension>
</xs:complexContent>
</xs:complexType>
My current (feeble) attempt at defining the schema for the rules node is below. However,
Can I nest xs:choice within xs:sequence? If, where do I specify the maxOccurs="unbounded" attribute?
Is there a better way to do this, such as an xs:sequence which specifies only the base type of its child elements?
<xs:element name="rules">
<xs:complexType>
<xs:sequence>
<xs:choice>
<xs:element name="bool" type="booleanRule" />
<xs:element name="string" type="stringRule" />
<xs:element name="other" type="someOtherRule" />
</xs:choice>
</xs:sequence>
</xs:complexType>
</xs:element>
