The DOMNode class

(PHP 5, PHP 7, PHP 8)

类摘要 class DOMNode { /* 属性 */ public readonly string $nodeName; public ?string $nodeValue; public readonly int $nodeType; public readonly ?DOMNode $parentNode; public readonly DOMNodeList $childNodes; public readonly ?DOMNode $firstChild; public readonly ?DOMNode $lastChild; public readonly ?DOMNode $previousSibling; public readonly ?DOMNode $nextSibling; public readonly ?DOMNamedNodeMap $attributes; public readonly ?DOMDocument $ownerDocument; public readonly ?string $namespaceURI; public string $prefix; public readonly ?string $localName; public readonly ?string $baseURI; public string $textContent; /* 方法 */ public appendChild(DOMNode $node): DOMNode|false public C14N(
    bool $exclusive = false,
    bool $withComments = false,
    ?array $xpath = null,
    ?array $nsPrefixes = null
): string|false public C14NFile(
    string $uri,
    bool $exclusive = false,
    bool $withComments = false,
    ?array $xpath = null,
    ?array $nsPrefixes = null
): int|false public cloneNode(bool $deep = false): DOMNode|false public getLineNo(): int public getNodePath(): ?string public hasAttributes(): bool public hasChildNodes(): bool public insertBefore(DOMNode $node, ?DOMNode $child = null): DOMNode|false public isDefaultNamespace(string $namespace): bool public isSameNode(DOMNode $otherNode): bool public isSupported(string $feature, string $version): bool public lookupNamespaceUri(string $prefix): string public lookupPrefix(string $namespace): ?string public normalize(): void public removeChild(DOMNode $child): DOMNode|false public replaceChild(DOMNode $node, DOMNode $child): DOMNode|false }

属性 nodeName

Returns the most accurate name for the current node type

nodeValue

The value of this node, depending on its type. Contrary to the W3C specification, the node value of DOMElement nodes is equal to DOMNode::textContent instead of null.

nodeType

Gets the type of the node. One of the predefined XML_xxx_NODE constants

parentNode

The parent of this node. If there is no such node, this returns null.

childNodes

A DOMNodeList that contains all children of this node. If there are no children, this is an empty DOMNodeList.

firstChild

The first child of this node. If there is no such node, this returns null.

lastChild

The last child of this node. If there is no such node, this returns null.

previousSibling

The node immediately preceding this node. If there is no such node, this returns null.

nextSibling

The node immediately following this node. If there is no such node, this returns null.

attributes

A DOMNamedNodeMap containing the attributes of this node (if it is a DOMElement) or null otherwise.

ownerDocument

The DOMDocument object associated with this node, or null if this node is a DOMDocument

namespaceURI

The namespace URI of this node, or null if it is unspecified.

prefix

The namespace prefix of this node, or null if it is unspecified.

localName

Returns the local part of the qualified name of this node.

baseURI

The absolute base URI of this node or null if the implementation wasn't able to obtain an absolute URI.

textContent

The text content of this node and its descendants.

更新日志 版本 说明 8.0.0 The unimplemented methods DOMNode::compareDocumentPosition(), DOMNode::isEqualNode(), DOMNode::getFeature(), DOMNode::setUserData() and DOMNode::getUserData() have been removed.

注释

注意:

此 DOM 扩展采用 UTF-8 编码。在 ISO-8859-1 编码下，使用 utf8_encode() 和 utf8_decode() 来处理，其它编码下使用 iconv 函数处理。

参见

» W3C specification of Node 目录DOMNode::appendChild — Adds new child at the end of the childrenDOMNode::C14N — Canonicalize nodes to a stringDOMNode::C14NFile — Canonicalize nodes to a fileDOMNode::cloneNode — Clones a nodeDOMNode::getLineNo — Get line number for a nodeDOMNode::getNodePath — Get an XPath for a nodeDOMNode::hasAttributes — Checks if node has attributesDOMNode::hasChildNodes — Checks if node has childrenDOMNode::insertBefore — Adds a new child before a reference nodeDOMNode::isDefaultNamespace — Checks if the specified namespaceURI is the default namespace or notDOMNode::isSameNode — Indicates if two nodes are the same nodeDOMNode::isSupported — Checks if feature is supported for specified versionDOMNode::lookupNamespaceUri — Gets the namespace URI of the node based on the prefixDOMNode::lookupPrefix — Gets the namespace prefix of the node based on the namespace URIDOMNode::normalize — Normalizes the nodeDOMNode::removeChild — Removes child from list of childrenDOMNode::replaceChild — Replaces a child

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User Contributed Notes 14 notes

up down 38 marc at ermshaus dot org ¶13 years ago It took me forever to find a mapping for the XML_*_NODE constants. So I thought, it'd be handy to paste it here:

1 XML_ELEMENT_NODE
2 XML_ATTRIBUTE_NODE
3 XML_TEXT_NODE
4 XML_CDATA_SECTION_NODE
5 XML_ENTITY_REFERENCE_NODE
6 XML_ENTITY_NODE
7 XML_PROCESSING_INSTRUCTION_NODE
8 XML_COMMENT_NODE
9 XML_DOCUMENT_NODE
10 XML_DOCUMENT_TYPE_NODE
11 XML_DOCUMENT_FRAGMENT_NODE
12 XML_NOTATION_NODE up down 19 David Rekowski ¶12 years ago You cannot simply overwrite $textContent, to replace the text content of a DOMNode, as the missing readonly flag suggests. Instead you have to do something like this:

<?php

$node->removeChild($node->firstChild);
$node->appendChild(new DOMText('new text content'));

?>

This example shows what happens:

<?php

$doc = DOMDocument::loadXML('<node>old content</node>');
$node = $doc->getElementsByTagName('node')->item(0);
echo "Content 1: ".$node->textContent."\n";

$node->textContent = 'new content';
echo "Content 2: ".$node->textContent."\n";

$newText = new DOMText('new content');

$node->appendChild($newText);
echo "Content 3: ".$node->textContent."\n";

$node->removeChild($node->firstChild);
$node->appendChild($newText);
echo "Content 4: ".$node->textContent."\n";

?>

The output is:

Content 1: old content // starting content
Content 2: old content // trying to replace overwriting $node->textContent
Content 3: old contentnew content // simply appending the new text node
Content 4: new content // removing firstchild before appending the new text node

If you want to have a CDATA section, use this:

<?php
$doc = DOMDocument::loadXML('<node>old content</node>');
$node = $doc->getElementsByTagName('node')->item(0);
$node->removeChild($node->firstChild);
$newText = $doc->createCDATASection('new cdata content');
$node->appendChild($newText);
echo "Content withCDATA: ".$doc->saveXML($node)."\n";
?> up down 15 R. Studer ¶12 years ago For clarification:
The assumingly 'discoverd' by previous posters and seemingly undocumented methods (.getElementsByTagName and .getAttribute) on this class (DOMNode) are in fact methods of the class DOMElement, which inherits from DOMNode.

See: http://www.php.net/manual/en/class.domelement.php up down 9 brian wildwoodassociates.info ¶13 years ago This class has a getAttribute method.

Assume that a DOMNode object $ref contained an anchor taken out of a DOMNode List.  Then

    $url = $ref->getAttribute('href');

would isolate the url associated with the href part of the anchor. up down 5 Steve K ¶12 years ago This class apparently also has a getElementsByTagName method.

I was able to confirm this by evaluating the output from DOMNodeList->item() against various tests with the is_a() function. up down 3 alastair dot dallas at gmail dot com ¶10 years ago The issues around mixed content took me some experimentation to remember, so I thought I'd add this note to save others time.

When your markup is something like: <div><p>First text.</p><ul><li><p>First bullet</p></li></ul></div>, you'll get XML_ELEMENT_NODEs that are quite regular. The <div> has children <p> and <ul> and the nodeValue for both <p>s yields the text you expect.

But when your markup is more like <p>This is <b>bold</b> and this is <i>italic</i>.</p>, you realize that the nodeValue for XML_ELEMENT_NODEs is not reliable. In this case, you need to look at the <p>'s child nodes. For this example, the <p> has children: #text, <b>, #text, <i>, #text.

In this example, the nodeValue of <b> and <i> is the same as their #text children. But you could have markup like: <p>This <b>is bold and <i>bold italic</i></b>, you see?</p>. In this case, you need to look at the children of <b>, which will be #text, <i>, because the nodeValue of <b> will not be sufficient.

XML_TEXT_NODEs have no children and are always named '#text'. Depending on how whitespace is handled, your tree may have "empty" #text nodes as children of <body> and elsewhere.

Attributes are nodes, but I had forgotten that they are not in the tree expressed by childNodes. Walking the full tree using childNodes will not visit any attribute nodes. up down 4 imranomar at gmail dot com ¶11 years ago Just discovered that node->nodeValue strips out all the tags up down 1 pizarropablo at gmail dot com ¶8 years ago In response to: alastair dot dallas at gmail dot com about "#text" nodes.
"#text" nodes appear when there are spaces or new lines between end tag and next initial tag.

Eg "<data><age>10</age>[SPACES]<other>20</other>[SPACES]</data>"

"data" childNodes has 4 childs:
- age = 10
- #text = spaces
- other = 20
- #text =  spaces up down 2 matt at lamplightdb dot co dot uk ¶13 years ago And apparently also a setAttribute method too:

$node->setAttribute( 'attrName' , 'value' ); up down 0 metanull ¶7 years ago Yet another DOMNode to php array conversion function.
Other ones on this page are generating too "complex" arrays; this one should keep the array as tidy as possible.
Note: make sure to set LIBXML_NOBLANKS when calling DOMDocument::load, loadXML or loadHTML
See: http://be2.php.net/manual/en/libxml.constants.php
See: http://be2.php.net/manual/en/domdocument.loadxml.php

<?php
         /**
         * Returns an array representation of a DOMNode
         * Note, make sure to use the LIBXML_NOBLANKS flag when loading XML into the DOMDocument
         * @param DOMDocument $dom
         * @param DOMNode $node
         * @return array
         */
        function nodeToArray( $dom, $node) {
            if(!is_a( $dom, 'DOMDocument' ) || !is_a( $node, 'DOMNode' )) {
                return false;
            }
            $array = false;
            if( empty( trim( $node->localName ))) {// Discard empty nodes
                return false;
            }
            if( XML_TEXT_NODE == $node->nodeType ) {
                return $node->nodeValue;
            }
            foreach ($node->attributes as $attr) {
                $array['@'.$attr->localName] = $attr->nodeValue;
            }
            foreach ($node->childNodes as $childNode) {
                if ( 1 == $childNode->childNodes->length && XML_TEXT_NODE == $childNode->firstChild->nodeType ) {
                    $array[$childNode->localName] = $childNode->nodeValue;
                }  else {
                    if( false !== ($a = self::nodeToArray( $dom, $childNode))) {
                        $array[$childNode->localName] =     $a;
                    }
                }
            }
            return $array;
        }
?> up down 0 matej dot golian at gmail dot com ¶8 years ago Here is a little function that truncates a DomNode to a specified number of text characters. I use it to generate HTML excerpts for my blog entries.

<?php

function makehtmlexcerpt(DomNode $html, $excerptlength)
{
$remove = 0;
$htmllength = strlen(html_entity_decode($html->textContent, ENT_QUOTES, 'UTF-8'));
$truncate = $htmllength - $excerptlength;
if($htmllength > $excerptlength)
{
if($html->hasChildNodes())
{
$children = $html->childNodes;
for($counter = 0; $counter < $children->length; $counter ++)
{
$child = $children->item($children->length - ($counter + 1));
$childlength = strlen(html_entity_decode($child->textContent, ENT_QUOTES, 'UTF-8'));
if($childlength <= $truncate)
{
$remove ++;
$truncate = $truncate - $childlength;
}
else
{
$child = makehtmlexcerpt($child, $childlength - $truncate);
break;
}
}
if($remove != 0)
{
for($counter = 0; $counter < $remove; $counter ++)
{
$html->removeChild($html->lastChild);
}
}
}
else
{
if($html->nodeName == '#text')
{
$html->nodeValue = substr(html_entity_decode($html->nodeValue, ENT_QUOTES, 'UTF-8'), 0, $htmllength - $truncate);
}
}
}
return $html;
}

?> up down -2 Anonymous ¶4 years ago It would be helpful if docs for concrete properties mentioned readonly status of some properties:
"
ownerDocument

    The DOMDocument object associated with this node.

" up down -2 zlk1214 at gmail dot com ¶6 years ago A function that can set the inner HTML without encoding error. $html can be broken content such as "<a ID=id20>ssss"
function setInnerHTML($node, $html) {
    removeChildren($node);
    if (empty($html)) {
        return;
    }
  
    $doc = $node->ownerDocument;
    $htmlclip = new DOMDocument();
    $htmlclip->loadHTML('<meta http-equiv="Content-Type" content="text/html;charset=utf-8"><div>' . $html . '</div>');
    $clipNode = $doc->importNode($htmlclip->documentElement->lastChild->firstChild, true);
    while ($item = $clipNode->firstChild) {
        $node->appendChild($item);
    }
} up down -9 I. Cook ¶12 years ago For a reference with more information about the XML DOM node types, see http://www.w3schools.com/dom/dom_nodetype.asp

(When using PHP DOMNode, these constants need to be prefaced with "XML_") add a note