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DOMXPath->evaluate()

DOMXPath->evaluate()

(no version information, might be only in CVS)

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

Popis

class DOMXPath {

mixed evaluate ( string expression [, DOMNode contextnode] )

}

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

Seznam parametrů

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.

Návratové hodnoty

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

Příklady

Příklad 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";

?>

Výše uvedený příklad vypíše:

There are 2 english books