版权声明：本文为博主原创文章，未经博主允许不得转载。 https://blog.csdn.net/wt1286331074/article/details/88422343
参考：http://www.php.cn/php-weizijiaocheng-376167.html （中文）
https://symfony.com/doc/current/components/dom_crawler.html （官方英文）
因为是项目中运用，首先composer下composer require symfony/dom-crawler然后use写代码
$html = <<<HTML
<body>
Hello World!
Hello Crawler!
<p class="p-1">我是p标签11</p>
<p class="p-2">我是p标签22</p>
<p class="p-3">
<a alt="first" href="www.first.com"><img src="www.img222.com" alt="tu1">独一</a>
<a ><img src="www.img.com" alt="tu2"></a>
</p>
</body>
HTML;
$crawler = new Crawler($html);
echo $crawler->filterXPath('//body/p')->text();// 获得里面的dom
// 获得内容里面重复的标签内容
foreach ($crawler->filterXPath('//body/p') as $i=>$node){
$c = new Crawler($node);
echo $c->filter('p')->text();
}
$nodeValues = $crawler->filterXPath('//body/p')->each(function (Crawler $node,$i){
return $node->text();
});
// 获得第二个p标签的class属性值
echo $crawler->filterXPath('//body/p')->last()->attr('class');
// 根据特定的class属性搜
echo $crawler->filterXPath('//p[@class="p-2"]')->text();
// 寻找，抽取属性
$dataArr = $crawler->filterXPath('//p[@class="p-3"]')->filter('a>img')->extract(array('alt'));