DOMXPath
PHP Manual

DOMXPath::evaluate

(PHP 5 >= 5.1.0)

DOMXPath::evaluate Evaluates the given XPath expression and returns a typed result if possible.

Описание

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

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

Параметри

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.

Връщани стойности

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

Примери

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";

?>

Примерът по-горе ще изведе:

There are 2 english books

Вж. също


DOMXPath
PHP Manual