Use <xs:all> in XML schema's complexType?

问题

I have the following XML complexTypes defined:

<xs:complexType name="loss">
    <xs:all>
        <xs:element name="lossCause" type="xs:string"/>
        <xs:element name="lossDate" type="xs:dateTime"/>
        <xs:element name="lossDescription" type="xs:string"/>
        <xs:element name="lossLocation" type="address" minOccurs="0"/>
        <xs:element name="lossTime" type="xs:string" minOccurs="0"/>
        <xs:element name="officials" minOccurs="0">
            <xs:complexType>
                <xs:sequence>
                    <xs:element name="official" type="official" minOccurs="0" maxOccurs="unbounded"/>
                </xs:sequence>
            </xs:complexType>
        </xs:element>
    </xs:all>
    <xs:attribute name="incidentOnly" type="xs:boolean" use="required"/>
    <xs:attribute name="lawsuit" type="xs:boolean" use="required"/>
</xs:complexType>

and:

<xs:complexType name="propLoss">
    <xs:complexContent>
        <xs:extension base="loss">
            <xs:all>
                <xs:element name="damageDescription" type="xs:string"/>
                <xs:element name="property" type="property"/>
                <xs:element name="responsibleParty" type="contact" minOccurs="0"/>
            </xs:all>
            <xs:attribute name="businessOperational" type="xs:boolean" use="required"/>
            <xs:attribute name="propertyLivable" type="xs:boolean" use="required"/>
            <xs:attribute name="weatherRelated" type="xs:boolean" use="required"/>
        </xs:extension>
    </xs:complexContent>
</xs:complexType>

However, upon validation, I get an error stating that the all model group isn't allowed within the loss complexType nor its extension propLoss definition. What is it that I'm doing wrong?

Thanks!

回答1:

A problem with propLoss is that you can't extend an all group in XML Schema (1.0). From the spec:

Note: This specification allows only appending, and not other kinds of extensions. This decision simplifies application processing required to cast instances from derived to base type. Future versions may allow more kinds of extension, requiring more complex transformations to effect casting.

Not sure what the problem with loss is unless it collateral damage from the propLoss error.

回答2:

Note that in XSD 1.1 all groups can be extended in the way shown here, with the meaning being that all of the children mentioned in either all-group must be present in any order. (That is, all-group 1 and all-group 2 get merged together into a single all-group with the concatenation of their children.)

来源：https://stackoverflow.com/questions/7603317/use-xsall-in-xml-schemas-complextype