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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.

Leírás

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

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

Paraméterek

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.

Visszatérési értékek

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

Példák

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";

?>

A fenti példa a következő kimenetet adja:

There are 2 english books

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