问题
I want to ensure that there are no duplicate book titles in the following xml:
<?xml version="1.0" encoding="UTF-8"?>
<books xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:noNamespaceSchemaLocation="books3.xsd">
<book>
<title>Book1</title>
</book>
<book>
<title>Book2</title>
</book>
<book>
<title>Book1</title> <!-- duplicate should not be allowed -->
</book>
</books>
I am using the following schema:
<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" elementFormDefault="qualified">
<xs:element name="books">
<xs:complexType>
<xs:sequence>
<xs:element maxOccurs="unbounded" ref="book"/>
</xs:sequence>
</xs:complexType>
<xs:unique name="testUnique">
<xs:selector xpath="book"/>
<xs:field xpath="title"/>
</xs:unique>
</xs:element>
<xs:element name="book">
<xs:complexType>
<xs:sequence>
<xs:element ref="title"/>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="title" type="xs:NCName"/>
</xs:schema>
oXygen XML editor tells me this is valid when I validate.
Can anybody see what I am doing wrong?
回答1:
the schema seems ok and should detect the duplicate. may be a bug in Oxygen?
you can try this site to validate your xml : http://www.xmlvalidation.com
and you'll see it finds errors in your xmldocument:
Duplicate unique value [Book1] declared for identity constraint of element "books"
来源:https://stackoverflow.com/questions/2386633/how-do-i-ensure-unique-element-values-in-an-xml-schema