[edit] Last updated: Fri, 10 Feb 2012

La classe DOMXPath

(PHP 5)

Introduction

Support de XPath 1.0.

Synopsis de la classe

DOMXPath {

/* Propriétés */

public DOMDocument $DOMXPath->document ;

/* Méthodes */

public DOMXPath::__construct ( DOMDocument $doc )

public mixed DOMXPath::evaluate ( string $expression [, DOMNode $contextnode [, bool $registerNodeNS = true ]] )

public DOMNodeList DOMXPath::query ( string $expression [, DOMNode $contextnode [, bool $registerNodeNS = true ]] )

public bool DOMXPath::registerNamespace ( string $prefix , string $namespaceURI )

public void DOMXPath::registerPhpFunctions ([ mixed $restrict ] )

}

Propriétés

document

Sommaire

DOMXPath::__construct — Crée un nouvel objet DOMXPath
DOMXPath::evaluate — Évalue une expression XPath donnée et retourne un résultat écrit si possible
DOMXPath::query — Évalue l'expression XPath donnée
DOMXPath::registerNamespace — Enregistre l'espace de noms avec l'objet DOMXPath
DOMXPath::registerPhpFunctions — Enregistre une fonction PHP comme fonction XPath

DOMXPath::__construct

DOMText::splitText

[edit] Last updated: Fri, 10 Feb 2012

add a note User Contributed Notes DOMXPath

dhz 05-Jan-2011 11:47


I just spent far too much time chasing this one....



When running an xpath query on a table be careful about table internal nodes (ie: <tr></tr>, and <td></td>).  If the master <table> tag is missing, then query() (and likely evaluate() also) will return unexpected results.



I had a DOMNode with a structure like this:



<td>

    <table></table>

    <table>

        <tr>

            <td></td>

        </tr>

        <tr>

            <td></td>

            <td></td>

        </tr>

    </table>

</td>



Upon which I was trying to do a relative query (ie: <?php $xpath_obj->query('my/x/path', $relative_node); ?>).



But because of the lone outer <td></td> tags, the inner tags were being invalidated, while the nodes were still recognized.  Meaning that the following query would work:



<?php $xpath_obj->query('*[2]/*[*[2]]', $relative_node); ?>



But when replacing any of the "*" tokens with the corresponding (and valid) "table", "tr", or "td" tokens the query would inexplicably break.

david at lionhead dot nl 11-Aug-2009 08:33


When using DOMXPath and having a default namespace. Consider using an intermediate function to add the default namespace to all queries:





<?php


// The default namespace: x:xmlns="http://..."


$path="/Book/Title";


$path=preg_replace("\/([a-zA-Z])","/x:$1",$path);





// Result: /x:Book/x:Title


?>

Mark Omohundro, ajamyajax dot com 14-Dec-2008 10:15


<?php

// to retrieve selected html data, try these DomXPath examples:



$file = $DOCUMENT_ROOT. "test.html";

$doc = new DOMDocument();

$doc->loadHTMLFile($file);



$xpath = new DOMXpath($doc);



// example 1: for everything with an id

//$elements = $xpath->query("//*[@id]");



// example 2: for node data in a selected id

//$elements = $xpath->query("/html/body/div[@id='yourTagIdHere']");



// example 3: same as above with wildcard

$elements = $xpath->query("*/div[@id='yourTagIdHere']");



if (!is_null($elements)) {

  foreach ($elements as $element) {

    echo "<br/>[". $element->nodeName. "]";



    $nodes = $element->childNodes;

    foreach ($nodes as $node) {

      echo $node->nodeValue. "\n";

    }

  }

}

?>

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