DOMDocument::createAttribute

(PHP 5, PHP 7, PHP 8)

DOMDocument::createAttributeCreate new attribute

说明

public DOMDocument::createAttribute ( string $localName ) : DOMAttr|false

This function creates a new instance of class DOMAttr. 此节点出现在文档中,除非是用诸如 DOMNode->appendChild() 等函数来将其插入。

参数

localName

The name of the attribute.

返回值

The new DOMAttr or false if an error occurred.

错误/异常

DOM_INVALID_CHARACTER_ERR

Raised if localName contains an invalid character.

参见

User Contributed Notes

Skateside 05-Apr-2013 04:16
This may be obvious to most people, but it gave me a few minutes of head-scratching before I figured it out, but ampersands need to be properly escaped as HTML entities.

<?php
$doc
= new DOMDocument('1.0', "UTF-8");

$invalid_elem = $doc->createElement('field', 'incorrect attribute');
$invalid_attr = $doc->createAttribute('name');
$invalid_attr->value = 'foo&bar';
$invalid_elem->appendChild($invalid_attr);
$doc->appendChild($invalid_elem);

$valid_elem = $doc->createElement('field', 'correct attribute');
$valid_attr = $doc->createAttribute('name');
$valid_attr->value = 'foo&amp;bar';
$valid_elem->appendChild($valid_attr);
$doc->appendChild($valid_elem);

?>

Will output:
<?xml version="1.0" encoding="UTF-8"?>
<field name="foo">incorrect attribute</field>
<field name="foo&bar">correct attribute</field>

As near as I can figure out, no exception is thrown for an invalid attribute. This will affect DOMDocuments created as HTML as well as XML.
Beerkeeper 09-Nov-2011 07:19
Just in case it isn't clear (like I had), an example:

<?php

$domDocument
= new DOMDocument('1.0', "UTF-8");
$domElement = $domDocument->createElement('field','some random data');
$domAttribute = $domDocument->createAttribute('name');

// Value for the created attribute
$domAttribute->value = 'attributevalue';

// Don't forget to append it to the element
$domElement->appendChild($domAttribute);

// Append it to the document itself
$domDocument->appendChild($domElement);

?>

Will output:
<?xml version="1.0" encoding="UTF-8"?>
<field name="attributevalue">some random data</field>