使用DOMXPath和函数查询php - use DOMXPath and function query php

use DOMXPath and function query php

本文关键字：查询 php 函数 DOMXPath 使用 | 更新日期: 2023-09-27

具有以下html代码部分：

<ul id="tree">
  <li>
    <a href="">first</a>
    <ul>
      <li><a href="">subfirst</a></li>
      <li><a href="">subsecond</a></li>
      <li><a href="">subthird</a></li>
    </ul>
  </li>
  <li>
    <a href="">second</a>
    <ul>
      <li><a href="">subfirst</a></li>
      <li><a href="">subsecond</a></li>
      <li><a href="">subthird</a></li>
    </ul>
  </li>
</ul>

需要解析此html代码并获取下一个（使用DOMXPath:：query（）和foreach（））

- first
-- subfirst
-- subsecond
-- subthird
- second
-- subfirst
-- subsecond
-- subthird

一段代码：

$xpath = new 'DOMXPath($html);
$catgs = $xpath->query('//*[@id="tree"]/li/a');
foreach ($catgs as $category) {
  // first level
  echo '- ' . mb_strtolower($category->nodeValue) . '<br>';
  // second level
  // don't know
}

提前感谢！

这就是DOMBLAZE的用途：

/* DOMBLAZE */ $doc->registerNodeClass("DOMElement","DOMBLAZE"); class DOMBLAZE extends DOMElement{public function __invoke($expression) {return $this->xpath($expression);} function xpath($expression){$result=(new DOMXPath($this->ownerDocument))->evaluate($expression,$this);return($result instanceof DOMNodeList)?new IteratorIterator($result):$result;}}
$list = $doc->getElementById('tree');
foreach ($list('./li') as $item) {
    echo '- ', $item('string(./a)'), "'n";
    foreach ($item('./ul/li') as $subitem) {
        echo '-- ', $subitem('string(./a)'), "'n";
    }
}

输出：

- first
-- subfirst
-- subsecond
-- subthird
- second
-- subfirst
-- subsecond
-- subthird

DOMBLAZE是穷人的FluentDOM。

对于第二级，您还可以使用另一个查询：

$dom = new DOMDocument();
$dom->loadHTML($markup);
$xpath = new DOMXpath($dom);
$elements = $xpath->query('//ul[@id="tree"]/li');
foreach($elements as $el) {
    $head = $xpath->query('./a', $el)->item(0)->nodeValue;
    echo "- $head <br/>";
    foreach($xpath->query('./ul/li/a', $el) as $sub) { // query the second level
        echo '-- ' . $sub->nodeValue . '<br/>';
    }
}

示例