PHP Manual: DOMXPath->evaluate()

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DOMXPath->evaluate()

(no version information, might be only in CVS)

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

Description

class DOMXPath {

mixed evaluate ( string expression [, DOMNode contextnode] )

}

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

Parameters

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.

Return Values

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

Examples

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";

?>

The above example will output:

There are 2 english books