如何通过symfony爬虫获取当前父节点之后的下一个节点？

Question

用于解析的 HTML 5 示例：

<div id="orderDetails">
    <div> ... any number of blocks with unnecessary stuff ... </div>
    <div>Label for important info</div>
    <table> ... some other block type ... </table>
    <div>Some very important info here</div>
    <div> ... any number of blocks with unnecessary stuff ... </div>
</div>

我的 PHP 代码如下所示：

$crawler = new \Symfony\Component\DomCrawler\Crawler($html);
$label = $crawler->filter('#orderDetails div:contains("Label for important info")');
$info = $label->parent()->next('div');
assert('Some very important info here' === $info->text(), 'Important info must be grabbed from HTML');

但不幸的是爬虫没有方法parent和next。但是..它parents给了我所有父节点==所有我无法区分的div。

所以在这种情况下我有两个问题：

1. 如何获取当前节点的父节点？不是所有节点，而是“实际”节点！
2. 如何使用类似next/水平遍历 dom prev？

谢谢。

Answer 1

故事

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经过深入研究源代码，我发现该方法nextAll()返回的不是“全部”，而是“一个”节点（$node = $this->getNode(0);）。

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这意味着如果我需要“当前之后的两个节点”，那么我必须编写$node->nextAll()->nextAll()->nextAll().

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搞什么？！这是超级奇怪的命名约定（0_0）。

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答案

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1. 如何获取当前节点的父节点？不是所有节点，而是“实际”节点！
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// This is only one parent node\n$parent = $node->parents();\n

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2. 如何使用 next/prev 的类似方式水平遍历 dom？
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// This is only one node \xe2\x80\x93\xc2\xa0next after current\n$next = $node->nextAll();\n// This is only one node \xe2\x80\x93\xc2\xa0previous before current\n$prev = $node->nextAll();\n// This is only one node \xe2\x80\x93\xc2\xa0next after two from current\n$nextAfterTwo = $node->nextAll()->nextAll()->nextAll();\n

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具体代码解决方案

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因此，由于所需的实现确实存在，问题的功能解决方案如下所示：

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/**\n * Returns sibling node that is after current and filtered with selector\n *\n * @param Crawler $start    Node from which start traverse\n * @param string  $selector CSS/XPath selector like in `Crawler::filter($selector)`\n *\n * @return Crawler Found node wrapped with Crawler\n *\n * @throws \\InvalidArgumentException When node not found\n */\nfunction getNextFiltered(Crawler $start, string $selector) : Crawler\n{\n    $count = $start->parents()->count();\n    $next  = $start->nextAll();\n    while ($count --> 0) {\n        $filtered = $next->filter($selector);\n        if ($filtered->count()) return $filtered;\n        $next = $next->nextAll();\n    }\n\n    throw new \\InvalidArgumentException(\'No node found\');\n}\n

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在我的例子中：

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$crawler = new Crawler($html);\n$label   = $crawler->filter(\'#orderDetails div:contains("Label for important info")\');\n$info    = getNextFiltered($label, \'div\');\nassert(\'Some very important info here\' === $info->text(), \'Important info must be grabbed from HTML\');\n

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