如何确保 XML 架构中的唯一元素值？
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How do I ensure unique element values in an XML schema?
提问by Nick Miller
I want to ensure that there are no duplicate book titles in the following xml:
我想确保以下 xml 中没有重复的书名：
<?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:
我正在使用以下架构：
<?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.
oXygen XML 编辑器在我验证时告诉我这是有效的。
Can anybody see what I am doing wrong?
谁能看到我做错了什么？
采纳答案by PierrOz
the schema seems ok and should detect the duplicate. may be a bug in Oxygen?
架构似乎没问题，应该检测到重复。可能是氧气的错误？
you can try this site to validate your xml : http://www.xmlvalidation.com
你可以试试这个网站来验证你的 xml：http: //www.xmlvalidation.com
and you'll see it finds errors in your xmldocument:
你会看到它在你的 xmldocument 中发现错误：
Duplicate unique value [Book1] declared for identity constraint of element "books"
为元素“books”的身份约束声明的重复唯一值 [Book1]
