PHP Dom not retrieving element
$code = '
<h1>Galeria </h1>
<div class="galeria">
<ul id="galeria_list">
<li>
<img src="img.jpg" width="350" height="350" />
<br />
Teste
</li>
</ul>
</div>';
$dom = new DOMDocument;
$dom->validateOnParse = true;
$dom->loadHTML($code);
var_dump($dom->getElementById('galeria_list'));
The var_dump always returns NULL. Anyone know why? I can clearly see the element with the id galeria_list in $cod开发者_开发技巧e. Why is this not getting the element?
And also, does anyone know how to prevent the domdocument from adding the <html> and <body> tags on the saveHTML method?
Thanks
It seems that loadhtml() does not "attach" the html dtd that defines id as an id-attribute to the DOM. But if the html document contains a DOCTYPE declaration it works as intended. (But my guess is you don't want to add a doctype and html skeleton, anyway:).
$code = '<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html><head><title>...</title></head>
<body>
<h1>Galeria </h1>
<div class="galeria">
<ul id="galeria_list">
<li>
<img src="img.jpg" width="350" height="350" />
<br />
Teste
</li>
</ul>
</div>
</body></html>';
$dom = new DOMDocument;
$dom->loadhtml($code);
var_dump($dom->getElementById('galeria_list'));
It seems that the DOMDocument will not play nice with HTML fragments. You may want to either consider the DOMDocumentFragment (as dnagirl suggests) or consider extending the DOMDocument.
After a little research, I've put together a simple extension that will achieve what you are asking:
class MyDOMDocument extends DOMDocument {
function getElementById($id) {
//thanks to: http://www.php.net/manual/en/domdocument.getelementbyid.php#96500
$xpath = new DOMXPath($this);
return $xpath->query("//*[@id='$id']")->item(0);
}
function output() {
// thanks to: http://www.php.net/manual/en/domdocument.savehtml.php#85165
$output = preg_replace('/^<!DOCTYPE.+?>/', '',
str_replace( array('<html>', '</html>', '<body>', '</body>'),
array('', '', '', ''), $this->saveHTML()));
return trim($output);
}
}
Usage
$dom = new MyDOMDocument();
$dom->loadHTML($code);
var_dump($dom->getElementById("galeria_list"));
echo $dom->output();
You might consider DOMDocumentFragment rather than DOMDocument if you don't want headers.
As for the id problem, this is from the manual:
<?php
$doc = new DomDocument;
// We need to validate our document before refering to the id
$doc->validateOnParse = true;
$doc->Load('book.xml');
echo "The element whose id is books is: " . $doc->getElementById('books')->tagName . "\n";
?>
validateOnParse is likely the issue.
Someone worked around this problem in the PHP manual by using XPath: http://us3.php.net/manual/en/domdocument.getelementbyid.php#96500
加载中,请稍侯......
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