Xpath 链接的 XML 值答案

【问题标题】：Xpath Linked XML ValuesXpath 链接的 XML 值
【发布时间】：2011-10-11 04:03:12
【问题描述】：

我有一个主 XML 列表，它链接到我需要从中提取的其他 XML 实体。以下是其中两个提要的示例：

    <news state="Trial">
       <newsListItem href="http://api.newsfeed.com/x/news/800614671/">
       <id>800614671</id>
       <publishDate>2011-10-10T14:17:08</publishDate>
       </newsListItem>
       <newsListItem....> // Many more news items
    </news>

newsListItem 的 url 指向二级 xml 文档，如下所示：

    <newsItem encoding="UTF-8">
       <id>800614671</id>
       <state>Trial</state>
       <publishDate>2011-10-10T14:17:08</publishDate>
       <createdDate>2011-10-10T13:18:02</createdDate>
       <lastModifiedDate>2011-10-10T14:18:38</lastModifiedDate>
       <headline>Woman stabbed to death in south London</headline>
       <extract>Officers have confirmed a woman has been stabbed to death in a Bexleyheath street this morning.</extract>
       <categories href="http://api.newsfeed.com/x/news/800614671/categories/"/>
       <text format="html"><p>By Guy Kilty</p>
         <p>A woman has been stabbed to death and another has been injured in an attack in south London, police have confirmed.</p>
         <p>Officers were called to a busy street near the Asda supermarket in the Broadway area of Bexleyheath at 08:30 BST this morning (October 10th) following reports that a woman had been stabbed.</p>
         <p>The first victim was found with a stab wound and died at the scene, while the second had been stabbed in the hand and was taken to hospital.</p>
         <p>A Metropolitan Police spokesman said: &quot;Officers and the London Ambulance Service arrived on the scene and found a woman suffering stab wounds, who was pronounced dead at 8.41am.</p>
         <p>&quot;A second female suffered a knife injury to her hand. One woman has been arrested in connection with the incident.&quot;</p>
         <p>Police had no immediate information about the age of any of the people involved or any reason for the attack.</p>
       </text>
    </newsItem>

是否可以在主提要上使用 XPath 从 href 中提取数据？我最初在看类似/news/newsListItem/@href/???/newsItem/headline 的东西，但我不确定那是正确的轨道。这甚至可以通过 XPath 实现吗？

任何建议将不胜感激。这是我第一次使用 XPath。

【问题讨论】：

不幸的是，我无法使用 php 解决这个问题。我似乎仅限于 1.0 功能。谢谢大家的回复。为每个人点赞（因为所有 3 个都是正确的）！

标签： php xml xpath

【解决方案1】：

很遗憾，这是不可能的。最好的办法是检索 href，加载第二个 xml 文件，然后检索您需要的信息。

【讨论】：

【解决方案2】：

有一个带有此签名的 XPath 函数 doc()：

fn:doc($uri as xs:string?) as document-node()?

它接受一个 URI 并返回一个文档节点。这应该有效；如果您需要更多详细信息，请告诉我。

【讨论】：

目前 PHP 只支持 XPath 1.0 函数

【解决方案3】：

您可能在问 fn:doc($uri as xs:string?) as document-node()? 函数（在 xPath 2.0 中可用）。不确定它是否有效 - 但您的请求可以重写为：

fn:doc(/news/newsListItem/@href)/newsItem/headline

【讨论】：

目前 PHP 只支持 XPath 1.0 函数
谢谢你 AurelioDeRosa。这也是我发现的！