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DOMDocument::createElement

(PHP 5, PHP 7, PHP 8)

DOMDocument::createElement新しい要素ノードを作成する

説明

public DOMDocument::createElement(string $localName, string $value = ""): DOMElement|false

この関数は、DOMElement クラスの新しいインスタンスを作成します。 このノードは、( DOMNode::appendChild() などで) 挿入されない限り、ドキュメント内にあらわれません。

パラメータ

localName

要素のタグ名。

value

要素の値。デフォルトでは、空の要素が作成されます。 その後に DOMElement::$nodeValue で値を設定することも可能です。

指定した値はすべてそのまま用いますが、エンティティ参照 < と > だけはエスケープします。& は手動でエスケープする必要があることに注意しましょう。 そうしないと、エンティティ参照の開始とみなされてしまいます。また、" はエスケープされません。

戻り値

新しい DOMElement クラスの新しいインスタンス、 あるいはエラーが発生した場合は false を返します。

エラー / 例外

DOM_INVALID_CHARACTER_ERR

localName が無効な文字を含んでいる場合に発生します。

例1 新しい要素を作成し、ルートとして挿入する

<?php

$dom
= new DOMDocument('1.0', 'utf-8');

$element = $dom->createElement('test', 'This is the root element!');

// 新しい要素をルート (ドキュメントの子要素) として挿入する
$dom->appendChild($element);

echo
$dom->saveXML();
?>

上の例の出力は以下となります。

<?xml version="1.0" encoding="utf-8"?>
<test>This is the root element!</test>

例2 & をエスケープせずに value に渡す例

<?php
$dom
= new DOMDocument('1.0', 'utf-8');
$element = $dom->createElement('foo', 'me & you');
$dom->appendChild($element);
echo
$dom->saveXML();
?>

上の例の出力は、 たとえば以下のようになります。

Warning: DOMDocument::createElement(): unterminated entity reference             you in /in/BjTCg on line 4
<?xml version="1.0" encoding="utf-8"?>
<foo/>

注意

注意:

valueエスケープされませんエスケープに対応した テキストノードを作るには DOMDocument::createTextNode() を使います。

参考

add a note

User Contributed Notes 9 notes

up
14
mikek dot nospam at nospam dot muonics dot com
17 years ago
With regard to the note below about needing htmlentities to avoid warnings about unterminated entity references, I thought it worthwhile to mention that that you don't need to with createTextNode and DOMText::__construct. If you mix both methods of setting text nodes and do (or don't) apply htmlentities consistently to all data to be displayed, you'll get &amp;s (or warnings and badly-formed xml).

It's probably in one's best interest to extend DOMElement and DOMDocument so that it creates a DOMText node and appends it, rather than passing it up to the DOMElement constructor. Otherwise, good luck using (or not using) htmlentities in all the right places in your code, especially as code changes get made.

<?php

class XDOMElement extends DOMElement {
function
__construct($name, $value = null, $namespaceURI = null) {
parent::__construct($name, null, $namespaceURI);
}
}

class
XDOMDocument extends DOMDocument {
function
__construct($version = null, $encoding = null) {
parent::__construct($version, $encoding);
$this->registerNodeClass('DOMElement', 'XDOMElement');
}

function
createElement($name, $value = null, $namespaceURI = null) {
$element = new XDOMElement($name, $value, $namespaceURI);
$element = $this->importNode($element);
if (!empty(
$value)) {
$element->appendChild(new DOMText($value));
}
return
$element;
}
}

$doc1 = new XDOMDocument();
$doc1_e1 = $doc1->createElement('foo', 'bar & baz');
$doc1->appendChild($doc1_e1);
echo
$doc1->saveXML();

$doc2 = new XDOMDocument();
$doc2_e1 = $doc2->createElement('foo');
$doc2->appendChild($doc2_e1);
$doc2_e1->appendChild($doc2->createTextNode('bar & baz'));
echo
$doc2->saveXML();

?>

Text specified in createElement:
<?xml version=""?>
<foo>bar &amp; baz</foo>

Text added via createTextNode:
<?xml version=""?>
<foo>bar &amp; baz</foo>
up
5
yasindagli at gmail dot com
14 years ago
To create elements with attributes,

<?php

function createElement($domObj, $tag_name, $value = NULL, $attributes = NULL)
{
$element = ($value != NULL ) ? $domObj->createElement($tag_name, $value) : $domObj->createElement($tag_name);

if(
$attributes != NULL )
{
foreach (
$attributes as $attr=>$val)
{
$element->setAttribute($attr, $val);
}
}

return
$element;
}

$dom = new DOMDocument('1.0', 'utf-8');

$elm = createElement($dom, 'foo', 'bar', array('attr_name'=>'attr_value'));

$dom->appendChild($elm);

echo
$dom->saveXML();

?>

outputs :
<?xml version="1.0" encoding="utf-8"?>
<foo attr_name="attr_value">bar</foo>
up
8
sergsokolenko at gmail dot com
17 years ago
To avoid warning message "unterminated entity reference" you may use htmlentities() for escaping supplied value:
<?php
//...
$dom->createElement('name', htmlentities($text))
//...
?>
up
6
funkathustra
12 years ago
Although the built-in DOM functions are great, since they're designed to support generic XML, generating HTML DOMs becomes particularly verbose. I ended up writing this function to drastically speed things up.
Instead of calling something like
<?php
$div
= $dom->createElement("div");
$div->setAttribute("class","MyClass");
$div->setAttribute("id","MyID");
$someOtherDiv->appendChild($div);
?>
you can accomplish the same thing with:
<?php
$div
= newElement("div", $someOtherDiv, "class=MyClass;id=MyID");
?>
The "key1=value;key2=value" syntax is really fast to use, but obviously doesn't hold up if your content has those characters in it. So, you can also pass it an array:
<?php
$div
= newElement("div", $someOtherDiv, array("class","MyClass"));
?>
Or an array of arrays, representing different attributes:
<?php
$div
= newElement("form", $someOtherDiv, array(array("method","get"), array("action","/refer/?id=5");
?>

Here's the function:

<?php
function newElement($type, $insertInto = NULL, $params=NULL, $content="")
{
$tempEl = $this->dom->createElement($type, $content);
if(
gettype($params) == "string" && strlen($params) > 0)
{
$attributesCollection =split(";", $params);
foreach(
$attributesCollection as $attribute)
{
$keyvalue = split("=", $attribute);
$tempEl->setAttribute($keyvalue[0], $keyvalue[1]);
}
}
if(
gettype($params) == "array")
{
if(
gettype($params[0]) == "array")
{
foreach(
$params as $attribute)
{
$tempEl->setAttribute($attribute[0], $attribute[1]);
}
} else {
$tempEl->setAttribute($params[0], $params[1]);
}
}
?>
up
2
tschmieder at bitworks dot de
9 years ago
Remember:

If you want to perform multiple actions with a new node, you may need to create a copy of it before

means:
## Create an address to an unique memory block !
$td = $dom->createElement('td');
## Change some things in this original unique pattern
$td->setAttribute('class', 'saldo');

## clone the unique pattern to two own one's
$td1 = clone $td;
$td2 = clone $td;

## alter properties in each one
$td1->nodeValue = 'Ich bin die erste neue Node';
$td2->nodeValue = 'Ich bin die zweite neue Node';

## find the parent element
$tr = $dom->getElementById('t001-tr001');
## find the first and the last child (here only for clearity)
$first = $tr->firstChild;
$last = $tr->lastChild;

## produce the new nodes
$newtd1 = $tr->insertBefore($td1, $first);
$newtd2 = $tr->appendChild($td2);

conclusion:
YOU NEED AN ORIGINAL NEW NODE FOR EACH ACTION!
up
3
lars dot c dot magnusson at gmail dot com
13 years ago
You may think insertBefore and insertAfter is a direct alternative for appendChild, this is not the case.

<?php
$dom
= new DOMDocument();
$dom->load($file);

$dom->appendChild($newNode); //Works fine
$dom->insertBefore($newNode, $refNode); //Will fail

$refNode->parentNode->insertBefore($newNode, $refNode); // thanx to yasindagli (first post)
?>
up
4
estill at gvtc dot com
16 years ago
Note that the second parameter (value), although convenient, is non-standard. You should create elements like this instead:

<?php
$doc
= new DOMDocument('1.0', 'iso-8859-1');

$root = $doc->createElement('test');
$doc->appendChild($root);

$root_text = $doc->createTextNode('This is the root element!');
$root->appendChild($root_text);

print
$doc->saveXML();
?>

Or, alternatively, extend the DOMDocument class and add your own custom, convenience method to avoid intruding on the standard:

<?php
class CustomDOMDocument extends DOMDocument {
function
createElementWithText($name, $child_text) {
// Creates an element with a child text node

// @param string $name element tag name
// @param string $child_text child node text

// @return object new element

$element = $this->createElement($name);

$element_text = $this->createTextNode($child_text);
$element->appendChild($element_text);

return
$element;
}
}

$doc = new CustomDOMDocument('1.0', 'iso-8859-1');

$root = $doc->createElementWithText('test', 'This is the root element!');
$doc->appendChild($root);

print
$doc->saveXML();
?>

Also use caution with (or avoid) the 'DOMElement->nodeValue' property. It can return some unexpected values and changing its value will replace (remove) all descendants of the element with a single text node. It's also non-standard; according to the DOM spec it should return NULL.
up
2
chris AT cmbuckley DOT co DOT uk
14 years ago
Note that the NUL character "\0" is not in the list of invalid characters for $name, so no error is triggered, but the tag name will be truncated at the null byte:

<?php

$dom
= new DOMDocument('1.0', 'utf-8');
$el = $dom->createElement('foo' . "\0" . 'bar', 'Hello World');
echo
$el->tagName; // outputs "foo"

?>
up
-1
dignat at yahoo dot com
6 years ago
To create an element with DomDocument and to escape ampersand in the value.

Do this:

$element = new DOMDocument('1.0', 'UTF-8');

$test = $element->createElement('text');

$test ->appendChild($element->createElement('name'))
->appendChild($element->createtextNode('& I am ampersand');
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