具有简单 html dom 的 Xpath 无法获取标签的 text(） - Xpath with simple html dom unable to get the text() of a tag

我想获取带有maindiv的内容，而无需更多标签，例如我想从给定的代码中废弃"哈佛朝圣者医疗保健公司为您带来的冬季溜冰鞋，提供白天和晚上的公共滑冰，是今年冬天机舱发烧的完美补救措施。我正在使用带有简单html dom的xpath，这是我的代码

foreach($dom->find('//*[@id="main"]/text()[1]') as $element){
    $details=$element;
}

但它既没有得到任何元素，也没有进入foreach。你能给我任何解决方案吗？

<div id="main">
    <div>a</div>
    <div>b</div>
    <div>c</div>
    <a name="abc"></a>Winter Skate brought to you by Harvard Pilgrim HealthCare, offering day and evening public skating, is the perfect remedy to cabin fever this winter.<br />
    <br />
    A fun and affordable activity for parents with children, Winter Skate is also an ideal lunch break getaway and a romantic addition to a dinner date at Patriot Place. <br />
    <br />
    The 60-by-140-foot, refrigerated ice surface is designed specifically for recreational skating and the professional surface is large enough to accommodate beginners and experts alike.<br />
    <br />
    On-site skate rentals, concessions and bathrooms are available and parking is free.<br />
    <br />
    <br />
    <b>Concessions</b><br />
    Dunkin Donuts will be on-site with coffee, hot chocolate and donuts available for purchase. Additionally, Patriot Place features 16 dining and quick service restaurants including: Bar Louie, Baskin Robbins, Blue Fin Lounge, CBS Scene, Davio’s, Five Guys Burgers, Godiva, Olive Garden, Qdoba, Red Robin, Skipjack’s, Studio 3, Tastings Wine Bar & Bistro, Tavolino Pizza Gourmet, Twenty8 Food & Spirits.<br />
    <br />
    NOTE: Hours may occasionally vary due to inclement weather, Patriots home games, or pre-scheduled private events – please check back or call 508-203-2100<br><br>
    <a name='hours' class='ranchor'></a>
</div>

SimpleHtmlDom 没有实现官方的 W3C DOM API。它使用 CSS 选择器，而不是 XPath。CSS 选择器不能用于选择文本节点，它们只匹配元素节点。

您可以使用 PHP 标准的本机 DOM 扩展：

$dom = new DOMDocument();
@$dom->loadHtml($html);
$xpath = new DOMXPath($dom);
var_dump(
  $xpath->evaluate('string(//*[@id="main"]/text()[normalize-space() != ""][1])')
);

输出：

string(149) "Winter Skate brought to you by Harvard Pilgrim HealthCare, offering day and evening public skating, is the perfect remedy to cabin fever this winter."

[normalize-space() != ""]是筛选仅包含空格的节点的条件。

string()将结果列表中的第一个节点强制转换为字符串，并避免了循环的需要。

DOMDocument::loadHTML()和DOMDocument::loadHTMLFile()尝试修复无效的 html 源。例如，如果它们不存在，则添加html和body。这可以更改 HTML，因此最好将 HTML 保存回字符串以获取新结构：

$html = <<<'HTML'
<div id="main" class="one" class="two">
    <div>a</div>
    <div>b</div>
    <div>c</div>
    <a name="abc"></a>Winter Skate brought to you by ...
HTML;
$dom = new DOMDocument();
@$dom->loadHtml($html);
echo $dom->saveHtml();

输出：

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" "http://www.w3.org/TR/REC-html40/loose.dtd">
<html><body><div id="main" class="one">
    <div>a</div>
    <div>b</div>
    <div>c</div>
    <a name="abc"></a>Winter Skate brought to you by ...</div></body></html>

此外，@ 会阻止来自 HTML 解析的错误和警告。这在大多数情况下都有效，但更好的方法是使用 libxml 函数并处理/记录错误：

$dom = new DOMDocument();
libxml_use_internal_errors(TRUE);
$dom->loadHtml($html);
var_dump(libxml_get_errors());

输出：

array(1) {
  [0]=>
  object(LibXMLError)#2 (6) {
    ["level"]=>
    int(2)
    ["code"]=>
    int(42)
    ["column"]=>
    int(39)
    ["message"]=>
    string(26) "Attribute class redefined
"
    ["file"]=>
    string(0) ""
    ["line"]=>
    int(1)
  }
}

如果它报告了一个空的源代码，你需要检查 DOMDocument：：loadHTMLFile 是否可以获取它，尝试使用 file_get_contents（）获取它。