DOMAttr::isId

(PHP 5, PHP 7)

DOMAttr::isId — Checks if attribute is a defined ID

说明

public DOMAttr::isId ( ) : bool

This function checks if the attribute is a defined ID.

According to the DOM standard this requires a DTD which defines the attribute ID to be of type ID. You need to validate your document with DOMDocument::validate or DOMDocument::validateOnParse before using this function.

返回值

成功时返回 true，或者在失败时返回 false。

范例

示例 #1 DOMAttr::isId() Example


<?php

$doc = new DomDocument;

// We need to validate our document before referring to the id
$doc->validateOnParse = true;
$doc->Load('book.xml');

// We retrieve the attribute named id of the chapter element
$attr = $doc->getElementsByTagName('chapter')->item(0)->getAttributeNode('id');

var_dump($attr->isId()); // bool(true)

?>