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Element an HTML or XML element

Availability

DOM Level 1 Core

Inherits from/Overrides

Node figs/U2192.gif Element

Subinterfaces

HTMLElement

Properties

readonly String tagName

The tag name of the element. This is the string "P" for an HTML <p> element, for example. For HTML documents, the tag name is returned in uppercase, regardless of its capitalization in the document source. XML documents are case-sensitive, and the tag name is returned exactly as it is written in the document source. This property has the same value as the nodeName property of the Node interface.

Methods

getAttribute( )

Returns the value of a named attribute as a string.

getAttributeNS( ) [DOM Level 2]

Returns the string value of an attribute specified by local name and namespace URI. Useful only with XML documents that use namespaces.

getAttributeNode( )

Returns the value of a named attribute as an Attr node.

getAttributeNodeNS( ) [DOM Level 2]

Returns the Attr value of an attribute specified by local name and namespace URI. Useful only with XML documents that use namespaces.

getElementsByTagName( )

Returns an array (technically, a NodeList) of all descendant Element nodes of this element that have the specified tag name, in the order in which they appear in the document.

getElementsByTagNameNS( ) [DOM Level 2]

Like getElementsByTagName( ), except that the element tag name is specified by local name and namespace URI. Useful only with XML documents that use namespaces.

hasAttribute( ) [DOM Level 2]

Returns true if this element has an attribute with the specified name, or false otherwise. Note that this method returns true if the named attribute is explicitly specified in the document source or if the document's DTD specifies a default value for the named attribute.

hasAttributeNS( ) [DOM Level 2]

Like hasAttribute( ), except that the attribute is specified by a combination of local name and namespace URI. This method is useful only with XML documents that use namespaces.

removeAttribute( )

Deletes the named attribute from this element. Note, however, that this method deletes only attributes that are explicitly specified in the document source for this element. If the DTD specifies a default value for this attribute, that default becomes the new value of the attribute.

removeAttributeNS( ) [DOM Level 2]

Like removeAttribute( ), except that the attribute to be removed is specified by a combination of local name and namespace URI. Useful only for XML documents that use namespaces.

removeAttributeNode( )

Removes the specified Attr node from the list of attributes for this element. Note that this works only to remove attributes that are explicitly specified in the document source for this attribute. If the DTD specifies a default value for the removed attribute, a new Attr node is created to represent the default value of the attribute.

setAttribute( )

Sets the named attribute to the specified string value. If an attribute with that name does not already exist, a new attribute is added to the element.

setAttributeNS( ) [DOM Level 2]

Like setAttribute( ), except that the attribute to be set is specified by the combination of a local name and a namespace URI. Useful only with XML documents that use namespaces.

setAttributeNode( )

Adds the specified Attr node to the list of attributes for this element. If an attribute with the same name already exists, its value is replaced.

setAttributeNodeNS( ) [DOM Level 2]

Like setAttributeNode( ), but this method is suitable for use with nodes returned by Document.createAttributeNS( ). Useful only with XML documents that use namespaces.

Description

The Element interface represents HTML or XML elements or tags. The tagName property specifies the name of the element. The getElementsByTagName( ) method provides a powerful way to locate element descendants of a given element that have a specified tag name. The various other methods of this interface provide access to the attributes of the element. If you give an element a unique identifier using the id attribute in your document source, you can then easily locate the Element node that represents that document element with the useful Document.getElementById( ) method. To create a new Element node for insertion into a document, use Document.createElement( ).

In HTML documents (and many XML documents) all attributes have simple string values, and you can use the simple methods getAttribute( ) and setAttribute( ) for any attribute manipulation you need to do.

If you are working with XML documents that may contain entity references as part of attribute values, you will have to work with Attr objects and their subtree of nodes. You can get and set the Attr object for an attribute with getAttributeNode( ) and setAttributeNode( ), or you can iterate through the Attr nodes in the attributes[] array of the Node interface. If you are working with an XML document that uses XML namespaces, you'll need to use the various methods whose names end with "NS".

In the DOM Level 1 specification, the normalize( ) method was part of the Element interface. In the Level 2 specification, normalize( ) is instead part of the Node interface. All Element nodes inherit this method and can still use it.

See Also

HTMLElement, Node

Type of

Attr.ownerElement, Document.documentElement

Passed to

Document.getOverrideStyle( ), AbstractView.getComputedStyle( )

Returned by

Document.createElement( ), Document.createElementNS( ), Document.getElementById( )

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