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DOMXPath->evaluate()

(No version information available, might be only in CVS)

DOMXPath->evaluate() — Evaluates the given XPath expression and returns a typed result if possible.

Popis

DOMXPath
mixed evaluate ( string $expression [, DOMNode $contextnode ] )

Executes the given XPath expression and returns a typed result if possible.

Parametre

expression

The XPath expression to execute.

contextnode

The optional contextnode can be specified for doing relative XPath queries. By default, the queries are relative to the root element.

Vrátené hodnoty

Returns a typed result if possible or a DOMNodeList containing all nodes matching the given XPath expression .

Príklady

Example#1 Getting the count of all the english books

<?php

$doc 
= new DOMDocument;

$doc->load('book.xml');

$xpath = new DOMXPath($doc);

$tbody $doc->getElementsByTagName('tbody')->item(0);

// our query is relative to the tbody node
$query 'count(row/entry[. = "en"])';

$entries $xpath->evaluate($query$tbody);
echo 
"There are $entries english books\n";

?>

Výstup horeuvedeného príkladu bude:

There are 2 english books

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