php 한글 메뉴얼 도움말 검색 사이트 Evaluates the given XPath expression and returns a typed result if possible [domxpath.evaluate]

설명

public mixed DOMXPath::evaluate ( string $expression [, DOMNode $contextnode [, bool $registerNodeNS = true ]] )

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

인수

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.
registerNodeNS: The optional registerNodeNS can be specified to disable automatic registration of the context node.

반환값

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

If the expression is malformed or the contextnode is invalid, DOMXPath::evaluate() returns FALSE.

변경점

버전	설명
5.3.3	The `registerNodeNS` parameter was added.

예제

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";

?>

위 예제의 출력:

There are 2 english books

참고

DOMXPath::query() - Evaluates the given XPath expression