使用 PHP 进行 Xpath 查询(取两个值) [英] Xpath query with PHP (take two values)

问题描述

这是我正在使用的 XML 代码:

Here's the XML code i'm working with:

<inventory>
        <drink>
                <lemonade supplier="mother" id="1">
                        <title>Super Lemonade</title>
                        <price>$2.50</price>
                        <amount>20</amount>
                </lemonade>
                <lemonade supplier="mike" id="4">
                        <title>Lemonade Plus</title>
                        <price>$3.00</price>
                        <amount>20</amount>
                </lemonade>
                <pop supplier="store" id="2">
                        <title>Poppys</title>
                        <price>$1.50</price>
                        <amount>10</amount>
                </pop>
        </drink>
</inventory>

然后我写了一个简单的代码来练习使用 XPath:

Then i wrote a simple code to practice working with XPath:

<?php
        $xmldoc = new DOMDocument();
        $xmldoc->load('sample.xml');

        $xpathvar = new Domxpath($xmldoc);

        $queryResult = $xpathvar->query('//lemonade/price');
        foreach($queryResult as $result){
                echo $result->textContent;
        }
?>

该代码运行良好，按预期输出所有柠檬水价格值.

That code is working well, outputting all the lemonade price values as expected.

现在我需要一个 XPATH 来获取数量 = 20 的所有项目的 TITLE 和 SUPPLIER.

Now I need a XPATH to get me the TITLE and SUPPLIER of all items with amount = 20.

我该怎么做?

谢谢

推荐答案

使用:

/*/*/*[amount = 20]/@supplier | /*/*/*[amount = 20]/title 

这个选择:

1. 作为 XML 文档顶部元素的孙子元素的任何元素的任何 supplier 属性(与 /inventory/drink/lemonade 相同)，但我喜欢编写较短的 XPath 表达式)，其 amount 子项具有可转换为数字 20 的字符串值.

1. Any supplier attribute of any element that is a grand-child of the top element of the XML document (the same as /inventory/drink/lemonade, but I like to write shorter XPath expressions), whose amount child has a string value that is castable to the number 20.

作为 XML 文档顶部元素的孙子元素的任何元素的任何 title 子元素(与 /inventory/drink/lemonade 相同)，但我喜欢编写较短的 XPath 表达式)，其 amount 子项具有可转换为数字 20 的字符串值.

Any title child of any element that is a grand-child of the top element of the XML document (the same as /inventory/drink/lemonade, but I like to write shorter XPath expressions), whose amount child has a string value that is castable to the number 20.

基于 XSLT 的验证:

<xsl:stylesheet version="1.0"
 xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
 <xsl:output method="text"/>

 <xsl:template match="node()|@*">
     <xsl:for-each select=
     "/*/*/*[amount = 20]/@supplier
    |
      /*/*/*[amount = 20]/title">

      <xsl:value-of select="."/>
      <xsl:text>&#xA;</xsl:text>
     </xsl:for-each>
 </xsl:template>
</xsl:stylesheet>

当此转换应用于提供的 XML 文档时:

<inventory>
    <drink>
        <lemonade supplier="mother" id="1">
            <title>Super Lemonade</title>
            <price>$2.50</price>
            <amount>20</amount>
        </lemonade>
        <lemonade supplier="mike" id="4">
            <title>Lemonade Plus</title>
            <price>$3.00</price>
            <amount>20</amount>
        </lemonade>
        <pop supplier="store" id="2">
            <title>Poppys</title>
            <price>$1.50</price>
            <amount>10</amount>
        </pop>
    </drink>
</inventory>

它计算 XPath 表达式并在单独的行上复制所选模式的值:

mother
Super Lemonade
mike
Lemonade Plus

请注意:

使用诸如 XPath Visualizer -- 成千上万的人使用它以有趣的方式学习 XPath.

Your learning of XPath can greatly be helped by using a tool such as the XPath Visualizer -- used by many thousands of people to learn XPath the fun way.

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