How can I execute XPath queries on DOMElements using PHP?
I'm trying to do Xpath queries on DOMElements but it doesn't seem to work. Here is the code
<html>
<div class="test aaa">
<div></div>
<div class="link">contains a link</div>
<div></div>
</div>
<div class="test bbb">
<div></div>
<div></div>
<div class="link">contains a link</div>
</div>
</html>
What I'm doing is this:
$dom = new DOMDocument();
$html = file_get_contents("file.html");
@$dom->loadHTML($html);
$xpath = new DOMXPath($dom);
$entries = $xpath->query("//div[contains(@class,'test')]");
if (!$entries->length > 0) {
echo "Nothing\n";
} else {
foreach ($entries as $entry) {
$link = $xpath->query('/div[@class=link]',$entry);
echo $link->item(0)->nodeValue;
// => PHP Notice: Trying to get property of non-object
}
}
Everything works fine up to $xpath->query('/div[@class=link], $entry);. I don't know how to use Xpath on a particular DOMElement ($entry).
How can I use xpath queries on DOMElement?开发者_JAVA技巧
It looks like you're trying to mix CSS selectors with XPath. You want to be using a predicate ([...]) looking at the value of the class attribute.
For example, your //div.link might look like //div[contains(concat(' ',normalize-space(@class),' '),' link ')].
Secondly, within the loop you try to make a query with a context node then ignore that by using an absolute location path (it starts with a slash).
Updated to reflect changes to the question:
Your second XPath expression (/div[@class=link]) is still a) absolute, and b) has an incorrect condition. You want to be asking for matching elements relative to the specified context node ($entry) with the class attribute having a string value of link.
So /div[@class=link] should become something like div[@class="link"], which searches children of the $entry elements (use .//div[...] or descendant::div[...] if you want to search deeper).
加载中,请稍侯......
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