使用XPath时获取孙子nodeValue

Question

我正在寻找一种检索孙子的nodeValue的方法。 我只有明确的权限才能访问“我对此课程有明确的权限”类，如下所示。 我该怎么做？

<class="I have unambiguous access to this class">
- <class="childClass">
-- <class="grandsonClass">

///////

function curlGet($url){
    $ch = curl_init($url);

    curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);
    curl_setopt($ch, CURLOPT_FOLLOWLOCATION, TRUE);
    curl_setopt($ch, CURLOPT_HTTPHEADER, array($url));

    $results = curl_exec($ch);

    curl_close($ch);
    return $results;
}


function returnXPathObject($item){
    $xmlPageDom = new DOMDocument();
    @$xmlPageDom->loadHTML($item);
    $xmlPageXPath = new DOMXPath($xmlPageDom);
    return $xmlPageXPath;
}

$examplePage = curlGet("www.example.com");
$exampleXPath = returnXPathObject($examplePage);

$rating = $exampleXPath->query("//span[@class='grandfather']"); // I can access this guy, but I want it's grandchild.

// get child of grandfather's child (grandson of grandfather)

Answer 1

您可以通过传递“祖父” $rating作为上下文元素来进行相对XPath查询：

$query = "./span[@class='childClass']/span[@class='grandsonClass']";
$grandSon = $exampleXPath->query($query, $rating);