xpath:选择中断标记前后的文本节点

DOMDocument 的 加载HTML() 方法可以很好地处理无效的HTML片段,因此您可以这样使用DOMXPath:

<?php

$html = 'text1
<br>
text2
<br/>
text3
<br/>
text4
<br>
text5';

echo "<pre>" . htmlentities($html) . "</pre><br>\n";

$dom = new DOMDocument();
// loadHtml() needs mb_convert_encoding() to work well with UTF-8 encoding
$dom->loadHtml(mb_convert_encoding($html, 'HTML-ENTITIES', "UTF-8"));

$xpath = new DOMXPath($dom);

echo "Text nodes preceding br:";
foreach($xpath->query('//text()[(following::br)]') as $node)
{
    var_dump($node->wholeText);
}

echo "Text nodes following br:";
foreach($xpath->query('//text()[(preceding::br)]') as $node)
{
    var_dump($node->wholeText);
}

echo "Text nodes following OR preceding br:";
foreach($xpath->query('//text()[(following::br) or (preceding::br)]') as $node)
{
    var_dump($node->wholeText);
}

您的示例不是可以对其运行XPath查询的有效XML
元素总是关闭的。

但是,通常要选择使用节点类型谓词,如//br/text()