xml-namespaces – 解析MSXML时引用未声明的命名空间前缀

Reference to undeclared namespace prefix: '%s'

微软msxml实现的问题？

我正在使用来自政府网站的XML Feed,其中包含我需要解析的值. xml包含命名空间：

<?xml version="1.0" encoding="ISO-8859-1"?>
<rdf:RDF
    xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
    xmlns="http://purl.org/rss/1.0/"
    xmlns:cb="http://www.cbwiki.net/wiki/index.php/Specification_1.1"
    xmlns:dc="http://purl.org/dc/elements/1.1/"
    xmlns:dcterms="http://purl.org/dc/terms/"
    xmlns:xsi="http://www.w3c.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.w3c.org/1999/02/22-rdf-syntax-ns#rdf.xsd">
    <item rdf:about="http://www.bankofcanada.ca/stats/rates_rss/STATIC_IEXE0101.xml">
        <cb:statistics>
            <cb:exchangeRate>
                <cb:value decimals="4">1.0351</cb:value>
                <cb:baseCurrency>CAD</cb:baseCurrency>
                <cb:targetCurrency>USD</cb:targetCurrency>
                <cb:rateType>Bank of Canada noon rate</cb:rateType>
                <cb:observationPeriod frequency="daily">2011-05-09T12:15:00-04:00</cb:observationPeriod>
            </cb:exchangeRate>
        </cb:statistics>
    </item>
</rdf:RDF>

运行XPath查询：

/rdf:RDF/item/cb:statistics/cb:exchangeRate/cb:targetCurrency

失败并显示错误：

Reference to undeclared namespace prefix: 'rdf'

编辑：

如果我编辑原始XML以删除所有使用命名空间：

<?xml version="1.0" encoding="ISO-8859-1"?>
<rdf>
    <item>
        <statistics>
            <exchangeRate>
                <value decimals="4">1.0351</value>
                <baseCurrency>CAD</baseCurrency>
                <targetCurrency>USD</targetCurrency>
                <rateType>Bank of Canada noon rate</rateType>
                <observationPeriod frequency="daily">2011-05-09T12:15:00-04:00</observationPeriod>
            </exchangeRate>
        </statistics>
    </item>
</rdf>

查询/ rdf / item / statistics / exchangeRate / baseCurrency不会失败,并返回节点：

<baseCurrency>CAD</baseCurrency>

如何让Microsoft XML使用命名空间？

编辑2

我已经尝试添加SelectionNamespaces到DOMDocument对象：

doc.setProperty('SelectionNamespaces','xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:cb="http://www.cbwiki.net/wiki/index.php/Specification_1.1"');

现在,xpath查询不会失败,但它也不返回任何节点：

nodes = doc.selectNodes('/rdf:RDF/item/cb:statistics/cb:exchangeRate/cb:targetCurrency');

也可以看看

> “undeclared reference to namespace prefix ” error
> XMLReader – How to handle undeclared namespace
> PRB: Specifying Fully Qualified Element Names in XPath Queries
> XPath not working properly.