dpkajqd31574096 2010-03-19 13:53
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PHP Dom没有检索元素

$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 $code. 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

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  • dpvmtdu364462 2010-03-19 14:22
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    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();
    
    本回答被题主选为最佳回答 , 对您是否有帮助呢?
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