解析HTML并获取所有h3之后的h2之前的下一个h2使用PHP

Question

我期待在文章中找到第一个h2.一旦找到,找到所有h3,直到找到下一个h2.冲洗并重复,直到找到所有标题和副标题.

在您立即将此问题标记或关闭为重复解析问题之前,请注意问题标题,因为这与基本节点检索无关.我已经把那部分搞定了.

我正在使用DOMDocument解析HTML DOMDocument::loadHTML(), DOMDocument::getElementsByTagName()并DOMDocument::saveHTML()检索文章的重要标题.

我的代码如下:

$matches = array();
$dom = new DOMDocument;
$dom->loadHTML($content);
foreach($dom->getElementsByTagName('h2') as $node) {
    $matches['heading-two'][] = $dom->saveHtml($node);
}
foreach($dom->getElementsByTagName('h3') as $node) {
    $matches['heading-three'][] = $dom->saveHtml($node);
}
if($matches){
    $this->key_points = $matches;
}

这给了我一个类似的输出:

array(
    'heading-two' => array(
        '<h2>Here is the first heading two</h2>',
        '<h2>Here is the SECOND heading two</h2>'
    ),
    'heading-three' => array(
        '<h3>Here is the first h3</h3>',
        '<h3>Here is the second h3</h3>',
        '<h3>Here is the third h3</h3>',
        '<h3>Here is the fourth h3</h3>',
    )
);

我希望有更多的东西:

array(
    '<h2>Here is the first heading two</h2>' => array(
        '<h3>Here is an h3 under the first h2</h3>',
        '<h3>Here is another h3 found under first h2, but after the first h3</h3>'
    ),
    '<h2>Here is the SECOND heading two</h2>' => array(
        '<h3>Here is an h3 under the SECOND h2</h3>',
        '<h3>Here is another h3 found under SECOND h2, but after the first h3</h3>'
    )
);

我并不是在寻找代码完成(如果你觉得通过这样做可以更好地帮助其他人 - 继续),但是或多或少的指导或建议正确的方向来完成一个嵌套数组,如上面的直接.

Answer 1

我假设所有标题都在DOM中处于同一级别,因此每个h3都是h2的兄弟.有了这个假设,你可以迭代h2的兄弟,直到遇到下一个h2:

foreach($dom->getElementsByTagName('h2') as $node) {
    $key = $dom->saveHtml($node);
    $matches[$key] = array();
    while(($node = $node->nextSibling) && $node->nodeName !== 'h2') {
        if($node->nodeName == 'h3') {
            $matches[$key][] = $dom->saveHtml($node);   
        }
    }
}