CODEWITHSUNDEEP
phpxpathdomdocument
Mike
Mike

Reputation: 2735

XPath/Domdocument check for child by class name

I am trying to find child nodes by a certain class name (divs with class name='foo') within a loop of DOMDocument nodes. If it exists it should set my foo value to 1:

My HTML $document looks like:

...
<div class="posts">Div Posts 1</div>
<div class="posts">Div Posts 2<div class="foo"></div></div>
<div class="posts">Div Posts 3</div>
<div class="posts">Div Posts 4<div class="foo"></div></div>
<div class="posts">Div Posts 5</div>
...

DOMDocument/Xpath ($document):

$html = array();
$document = new \DOMDocument();
$document->loadHTMLFile($url); // loads html from above
$xpath = new \DOMXPath($document);

$i=0;
foreach ($xpath->query(Parser::cssToXpath('.posts')) as $node) {
    $html['posts'][$i]['content'] = $node->nodeValue;  
    // check if child node with class name 'foo' exists => doesn't work :(
    $children = $node->getElementsByTagName('foo');
    if($children)
        $html['posts'][$i]['foo'] = '1';
    else
        $html['posts'][$i]['foo'] = '0';
    $i++;
}

Output:

[posts] => Array
    (
        [0] => Array
            (
                [content] => Div class Posts 1
                [foo] => 1
            )

        [1] => Array
            (
                [content] => Div class Posts 2
                [foo] => 1
            )

        [2] => Array
            (
                [content] => Div class Posts 3
                [foo] => 1
            )

        [3] => Array
            (
                [content] => Div class Posts 4
                [foo] => 1
            )

        [4] => Array
            (
                [content] => Div class Posts 5
                [foo] => 1
            )

    )

getElementsByTagName() might not be the right method for that, but I tried different methods already and don't find the right one. :(

Upvotes: 2

Views: 7560

Answers (2)

VolkerK
VolkerK

Reputation: 96159

According to your comment

Hm yes but still doesn't work unfortunately. Eventually I need to know which .posts div has the child element 'foo' because I need to analyze the content of that parent and also need to replace it later
to the previous answer your predicate is probably:

a) select div elements
b) with attribute class=posts
c) and with a child element div
d) which has attribute class=foo

as xpath expression:

a) //div
b) //div[ @class="posts" ]
c) //div[ @class="posts" and div ]
d) //div[ @class="posts" and div[ @class="foo" ] ]

e.g.

<?php
$doc = new DOMDocument;
$doc->loadhtml( getData() );
$xpath = new DOMXPath($doc);   

/*
use something like
    //div[contains(concat(' ',normalize-space(@class),' '),' post ')]
if the html element may have class="post lalala"
*/
foreach( $xpath->query('//div[@class="posts" and div[@class="foo"]]') as $post) {
    while ( $post->firstChild ) {
        $post->removeChild( $post->firstChild );
    }   
    $post->appendChild( $doc->createElement('span', 'The quick fox....') );
}
echo $doc->savehtml();


function getData() {
    return <<< eoh
<html><head><title>...</title></head><body>
    <div class="posts">Div Posts 1</div>
    <div class="posts">Div Posts 2<div class="foo"></div></div>
    <div class="posts">Div Posts 3</div>
    <div class="posts">Div Posts 4<div class="foo"></div></div>
    <div class="posts">Div Posts 5</div>
</body></html>
eoh;
}

prints

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" "http://www.w3.org/TR/REC-html40/loose.dtd">
<html><head><title>...</title></head><body>
    <div class="posts">Div Posts 1</div>
    <div class="posts"><span>The quick fox....</span></div>
    <div class="posts">Div Posts 3</div>
    <div class="posts"><span>The quick fox....</span></div>
    <div class="posts">Div Posts 5</div>
</body></html>

Upvotes: 2

Kirill Polishchuk
Kirill Polishchuk

Reputation: 56162

Use this XPath to find all div elements with class foo

//div[@class = 'foo']

To be more specific, use this:

//div[@class = 'posts']/div[@class = 'foo']

Upvotes: 1

Related Questions