Interface Element
- All Superinterfaces:
Node
- All Known Subinterfaces:
HTMLAnchorElement, HTMLAppletElement, HTMLAreaElement, HTMLBaseElement, HTMLBaseFontElement, HTMLBodyElement, HTMLBRElement, HTMLButtonElement, HTMLDirectoryElement, HTMLDivElement, HTMLDListElement, HTMLElement, HTMLFieldSetElement, HTMLFontElement, HTMLFormElement, HTMLFrameElement, HTMLFrameSetElement, HTMLHeadElement, HTMLHeadingElement, HTMLHRElement, HTMLHtmlElement, HTMLIFrameElement, HTMLImageElement, HTMLInputElement, HTMLIsIndexElement, HTMLLabelElement, HTMLLegendElement, HTMLLIElement, HTMLLinkElement, HTMLMapElement, HTMLMenuElement, HTMLMetaElement, HTMLModElement, HTMLObjectElement, HTMLOListElement, HTMLOptGroupElement, HTMLOptionElement, HTMLParagraphElement, HTMLParamElement, HTMLPreElement, HTMLQuoteElement, HTMLScriptElement, HTMLSelectElement, HTMLStyleElement, HTMLTableCaptionElement, HTMLTableCellElement, HTMLTableColElement, HTMLTableElement, HTMLTableRowElement, HTMLTableSectionElement, HTMLTextAreaElement, HTMLTitleElement, HTMLUListElement
- All Known Implementing Classes:
IIOMetadataNode
The
Element
interface represents an element in an HTML or XML
document. Elements may have attributes associated with them; since the
Element
interface inherits from Node
, the
generic Node
interface attribute attributes
may
be used to retrieve the set of all attributes for an element. There are
methods on the Element
interface to retrieve either an
Attr
object by name or an attribute value by name. In XML,
where an attribute value may contain entity references, an
Attr
object should be retrieved to examine the possibly
fairly complex sub-tree representing the attribute value. On the other
hand, in HTML, where all attributes have simple string values, methods to
directly access an attribute value can safely be used as a convenience.
Note: In DOM Level 2, the method normalize
is
inherited from the Node
interface where it was moved.
See also the Document Object Model (DOM) Level 3 Core Specification.
- Since:
- 1.4, DOM Level 2
-
Field Summary
Fields declared in interface Node
ATTRIBUTE_NODE, CDATA_SECTION_NODE, COMMENT_NODE, DOCUMENT_FRAGMENT_NODE, DOCUMENT_NODE, DOCUMENT_POSITION_CONTAINED_BY, DOCUMENT_POSITION_CONTAINS, DOCUMENT_POSITION_DISCONNECTED, DOCUMENT_POSITION_FOLLOWING, DOCUMENT_POSITION_IMPLEMENTATION_SPECIFIC, DOCUMENT_POSITION_PRECEDING, DOCUMENT_TYPE_NODE, ELEMENT_NODE, ENTITY_NODE, ENTITY_REFERENCE_NODE, NOTATION_NODE, PROCESSING_INSTRUCTION_NODE, TEXT_NODE
Modifier and TypeFieldDescriptionstatic final short
The node is anAttr
.static final short
The node is aCDATASection
.static final short
The node is aComment
.static final short
The node is aDocumentFragment
.static final short
The node is aDocument
.static final short
The node is contained by the reference node.static final short
The node contains the reference node.static final short
The two nodes are disconnected.static final short
The node follows the reference node.static final short
The determination of preceding versus following is implementation-specific.static final short
The second node precedes the reference node.static final short
The node is aDocumentType
.static final short
The node is anElement
.static final short
The node is anEntity
.static final short
The node is anEntityReference
.static final short
The node is aNotation
.static final short
The node is aProcessingInstruction
.static final short
The node is aText
node. -
Method Summary
Modifier and TypeMethodDescriptiongetAttribute
(String name) Retrieves an attribute value by name.getAttributeNode
(String name) Retrieves an attribute node by name.getAttributeNodeNS
(String namespaceURI, String localName) Retrieves anAttr
node by local name and namespace URI.getAttributeNS
(String namespaceURI, String localName) Retrieves an attribute value by local name and namespace URI.getElementsByTagName
(String name) Returns aNodeList
of all descendantElements
with a given tag name, in document order.getElementsByTagNameNS
(String namespaceURI, String localName) Returns aNodeList
of all the descendantElements
with a given local name and namespace URI in document order.The type information associated with this element.The name of the element.boolean
hasAttribute
(String name) Returnstrue
when an attribute with a given name is specified on this element or has a default value,false
otherwise.boolean
hasAttributeNS
(String namespaceURI, String localName) Returnstrue
when an attribute with a given local name and namespace URI is specified on this element or has a default value,false
otherwise.void
removeAttribute
(String name) Removes an attribute by name.removeAttributeNode
(Attr oldAttr) Removes the specified attribute node.void
removeAttributeNS
(String namespaceURI, String localName) Removes an attribute by local name and namespace URI.void
setAttribute
(String name, String value) Adds a new attribute.setAttributeNode
(Attr newAttr) Adds a new attribute node.setAttributeNodeNS
(Attr newAttr) Adds a new attribute.void
setAttributeNS
(String namespaceURI, String qualifiedName, String value) Adds a new attribute.void
setIdAttribute
(String name, boolean isId) If the parameterisId
istrue
, this method declares the specified attribute to be a user-determined ID attribute .void
setIdAttributeNode
(Attr idAttr, boolean isId) If the parameterisId
istrue
, this method declares the specified attribute to be a user-determined ID attribute .void
setIdAttributeNS
(String namespaceURI, String localName, boolean isId) If the parameterisId
istrue
, this method declares the specified attribute to be a user-determined ID attribute .Methods declared in interface Node
appendChild, cloneNode, compareDocumentPosition, getAttributes, getBaseURI, getChildNodes, getFeature, getFirstChild, getLastChild, getLocalName, getNamespaceURI, getNextSibling, getNodeName, getNodeType, getNodeValue, getOwnerDocument, getParentNode, getPrefix, getPreviousSibling, getTextContent, getUserData, hasAttributes, hasChildNodes, insertBefore, isDefaultNamespace, isEqualNode, isSameNode, isSupported, lookupNamespaceURI, lookupPrefix, normalize, removeChild, replaceChild, setNodeValue, setPrefix, setTextContent, setUserData
Modifier and TypeMethodDescriptionappendChild
(Node newChild) Adds the nodenewChild
to the end of the list of children of this node.cloneNode
(boolean deep) Returns a duplicate of this node, i.e., serves as a generic copy constructor for nodes.short
compareDocumentPosition
(Node other) Compares the reference node, i.e. the node on which this method is being called, with a node, i.e. the one passed as a parameter, with regard to their position in the document and according to the document order.ANamedNodeMap
containing the attributes of this node (if it is anElement
) ornull
otherwise.The absolute base URI of this node ornull
if the implementation wasn't able to obtain an absolute URI.ANodeList
that contains all children of this node.getFeature
(String feature, String version) This method returns a specialized object which implements the specialized APIs of the specified feature and version, as specified in .The first child of this node.The last child of this node.Returns the local part of the qualified name of this node.The namespace URI of this node, ornull
if it is unspecified (see ).The node immediately following this node.The name of this node, depending on its type; see the table above.short
A code representing the type of the underlying object, as defined above.The value of this node, depending on its type; see the table above.TheDocument
object associated with this node.The parent of this node.The namespace prefix of this node, ornull
if it is unspecified.The node immediately preceding this node.This attribute returns the text content of this node and its descendants.getUserData
(String key) Retrieves the object associated to a key on a this node.boolean
Returns whether this node (if it is an element) has any attributes.boolean
Returns whether this node has any children.insertBefore
(Node newChild, Node refChild) Inserts the nodenewChild
before the existing child noderefChild
.boolean
isDefaultNamespace
(String namespaceURI) This method checks if the specifiednamespaceURI
is the default namespace or not.boolean
isEqualNode
(Node arg) Tests whether two nodes are equal.boolean
isSameNode
(Node other) Returns whether this node is the same node as the given one.boolean
isSupported
(String feature, String version) Tests whether the DOM implementation implements a specific feature and that feature is supported by this node, as specified in .lookupNamespaceURI
(String prefix) Look up the namespace URI associated to the given prefix, starting from this node.lookupPrefix
(String namespaceURI) Look up the prefix associated to the given namespace URI, starting from this node.void
Puts allText
nodes in the full depth of the sub-tree underneath thisNode
, including attribute nodes, into a "normal" form where only structure (e.g., elements, comments, processing instructions, CDATA sections, and entity references) separatesText
nodes, i.e., there are neither adjacentText
nodes nor emptyText
nodes.removeChild
(Node oldChild) Removes the child node indicated byoldChild
from the list of children, and returns it.replaceChild
(Node newChild, Node oldChild) Replaces the child nodeoldChild
withnewChild
in the list of children, and returns theoldChild
node.void
setNodeValue
(String nodeValue) The value of this node, depending on its type; see the table above.void
The namespace prefix of this node, ornull
if it is unspecified.void
setTextContent
(String textContent) This attribute returns the text content of this node and its descendants.setUserData
(String key, Object data, UserDataHandler handler) Associate an object to a key on this node.
-
Method Details
-
getTagName
String getTagName()The name of the element. IfNode.localName
is different fromnull
, this attribute is a qualified name. For example, in:<elementExample id="demo"> ... </elementExample> ,
tagName
has the value"elementExample"
. Note that this is case-preserving in XML, as are all of the operations of the DOM. The HTML DOM returns thetagName
of an HTML element in the canonical uppercase form, regardless of the case in the source HTML document. -
getAttribute
-
setAttribute
Adds a new attribute. If an attribute with that name is already present in the element, its value is changed to be that of the value parameter. This value is a simple string; it is not parsed as it is being set. So any markup (such as syntax to be recognized as an entity reference) is treated as literal text, and needs to be appropriately escaped by the implementation when it is written out. In order to assign an attribute value that contains entity references, the user must create anAttr
node plus anyText
andEntityReference
nodes, build the appropriate subtree, and usesetAttributeNode
to assign it as the value of an attribute.
To set an attribute with a qualified name and namespace URI, use thesetAttributeNS
method.- Parameters:
name
- The name of the attribute to create or alter.value
- Value to set in string form.- Throws:
DOMException
- INVALID_CHARACTER_ERR: Raised if the specified name is not an XML name according to the XML version in use specified in theDocument.xmlVersion
attribute.
NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly.
-
removeAttribute
Removes an attribute by name. If a default value for the removed attribute is defined in the DTD, a new attribute immediately appears with the default value as well as the corresponding namespace URI, local name, and prefix when applicable. The implementation may handle default values from other schemas similarly but applications should useDocument.normalizeDocument()
to guarantee this information is up-to-date.
If no attribute with this name is found, this method has no effect.
To remove an attribute by local name and namespace URI, use theremoveAttributeNS
method.- Parameters:
name
- The name of the attribute to remove.- Throws:
DOMException
- NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly.
-
getAttributeNode
Retrieves an attribute node by name.
To retrieve an attribute node by qualified name and namespace URI, use thegetAttributeNodeNS
method.- Parameters:
name
- The name (nodeName
) of the attribute to retrieve.- Returns:
- The
Attr
node with the specified name (nodeName
) ornull
if there is no such attribute.
-
setAttributeNode
Adds a new attribute node. If an attribute with that name (nodeName
) is already present in the element, it is replaced by the new one. Replacing an attribute node by itself has no effect.
To add a new attribute node with a qualified name and namespace URI, use thesetAttributeNodeNS
method.- Parameters:
newAttr
- TheAttr
node to add to the attribute list.- Returns:
- If the
newAttr
attribute replaces an existing attribute, the replacedAttr
node is returned, otherwisenull
is returned. - Throws:
DOMException
- WRONG_DOCUMENT_ERR: Raised ifnewAttr
was created from a different document than the one that created the element.
NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly.
INUSE_ATTRIBUTE_ERR: Raised ifnewAttr
is already an attribute of anotherElement
object. The DOM user must explicitly cloneAttr
nodes to re-use them in other elements.
-
removeAttributeNode
Removes the specified attribute node. If a default value for the removedAttr
node is defined in the DTD, a new node immediately appears with the default value as well as the corresponding namespace URI, local name, and prefix when applicable. The implementation may handle default values from other schemas similarly but applications should useDocument.normalizeDocument()
to guarantee this information is up-to-date.- Parameters:
oldAttr
- TheAttr
node to remove from the attribute list.- Returns:
- The
Attr
node that was removed. - Throws:
DOMException
- NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly.
NOT_FOUND_ERR: Raised ifoldAttr
is not an attribute of the element.
-
getElementsByTagName
-
getAttributeNS
Retrieves an attribute value by local name and namespace URI.
Per [XML Namespaces] , applications must use the valuenull
as thenamespaceURI
parameter for methods if they wish to have no namespace.- Parameters:
namespaceURI
- The namespace URI of the attribute to retrieve.localName
- The local name of the attribute to retrieve.- Returns:
- The
Attr
value as a string, or the empty string if that attribute does not have a specified or default value. - Throws:
DOMException
- NOT_SUPPORTED_ERR: May be raised if the implementation does not support the feature"XML"
and the language exposed through the Document does not support XML Namespaces (such as [HTML 4.01]).- Since:
- 1.4, DOM Level 2
-
setAttributeNS
Adds a new attribute. If an attribute with the same local name and namespace URI is already present on the element, its prefix is changed to be the prefix part of thequalifiedName
, and its value is changed to be thevalue
parameter. This value is a simple string; it is not parsed as it is being set. So any markup (such as syntax to be recognized as an entity reference) is treated as literal text, and needs to be appropriately escaped by the implementation when it is written out. In order to assign an attribute value that contains entity references, the user must create anAttr
node plus anyText
andEntityReference
nodes, build the appropriate subtree, and usesetAttributeNodeNS
orsetAttributeNode
to assign it as the value of an attribute.
Per [XML Namespaces] , applications must use the valuenull
as thenamespaceURI
parameter for methods if they wish to have no namespace.- Parameters:
namespaceURI
- The namespace URI of the attribute to create or alter.qualifiedName
- The qualified name of the attribute to create or alter.value
- The value to set in string form.- Throws:
DOMException
- INVALID_CHARACTER_ERR: Raised if the specified qualified name is not an XML name according to the XML version in use specified in theDocument.xmlVersion
attribute.
NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly.
NAMESPACE_ERR: Raised if thequalifiedName
is malformed per the Namespaces in XML specification, if thequalifiedName
has a prefix and thenamespaceURI
isnull
, if thequalifiedName
has a prefix that is "xml" and thenamespaceURI
is different from " http://www.w3.org/XML/1998/namespace", if thequalifiedName
or its prefix is "xmlns" and thenamespaceURI
is different from "http://www.w3.org/2000/xmlns/", or if thenamespaceURI
is "http://www.w3.org/2000/xmlns/" and neither thequalifiedName
nor its prefix is "xmlns".
NOT_SUPPORTED_ERR: May be raised if the implementation does not support the feature"XML"
and the language exposed through the Document does not support XML Namespaces (such as [HTML 4.01]).- Since:
- 1.4, DOM Level 2
-
removeAttributeNS
Removes an attribute by local name and namespace URI. If a default value for the removed attribute is defined in the DTD, a new attribute immediately appears with the default value as well as the corresponding namespace URI, local name, and prefix when applicable. The implementation may handle default values from other schemas similarly but applications should useDocument.normalizeDocument()
to guarantee this information is up-to-date.
If no attribute with this local name and namespace URI is found, this method has no effect.
Per [XML Namespaces] , applications must use the valuenull
as thenamespaceURI
parameter for methods if they wish to have no namespace.- Parameters:
namespaceURI
- The namespace URI of the attribute to remove.localName
- The local name of the attribute to remove.- Throws:
DOMException
- NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly.
NOT_SUPPORTED_ERR: May be raised if the implementation does not support the feature"XML"
and the language exposed through the Document does not support XML Namespaces (such as [HTML 4.01]).- Since:
- 1.4, DOM Level 2
-
getAttributeNodeNS
Retrieves anAttr
node by local name and namespace URI.
Per [XML Namespaces] , applications must use the valuenull
as thenamespaceURI
parameter for methods if they wish to have no namespace.- Parameters:
namespaceURI
- The namespace URI of the attribute to retrieve.localName
- The local name of the attribute to retrieve.- Returns:
- The
Attr
node with the specified attribute local name and namespace URI ornull
if there is no such attribute. - Throws:
DOMException
- NOT_SUPPORTED_ERR: May be raised if the implementation does not support the feature"XML"
and the language exposed through the Document does not support XML Namespaces (such as [HTML 4.01]).- Since:
- 1.4, DOM Level 2
-
setAttributeNodeNS
Adds a new attribute. If an attribute with that local name and that namespace URI is already present in the element, it is replaced by the new one. Replacing an attribute node by itself has no effect.
Per [XML Namespaces] , applications must use the valuenull
as thenamespaceURI
parameter for methods if they wish to have no namespace.- Parameters:
newAttr
- TheAttr
node to add to the attribute list.- Returns:
- If the
newAttr
attribute replaces an existing attribute with the same local name and namespace URI, the replacedAttr
node is returned, otherwisenull
is returned. - Throws:
DOMException
- WRONG_DOCUMENT_ERR: Raised ifnewAttr
was created from a different document than the one that created the element.
NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly.
INUSE_ATTRIBUTE_ERR: Raised ifnewAttr
is already an attribute of anotherElement
object. The DOM user must explicitly cloneAttr
nodes to re-use them in other elements.
NOT_SUPPORTED_ERR: May be raised if the implementation does not support the feature"XML"
and the language exposed through the Document does not support XML Namespaces (such as [HTML 4.01]).- Since:
- 1.4, DOM Level 2
-
getElementsByTagNameNS
Returns aNodeList
of all the descendantElements
with a given local name and namespace URI in document order.- Parameters:
namespaceURI
- The namespace URI of the elements to match on. The special value "*" matches all namespaces.localName
- The local name of the elements to match on. The special value "*" matches all local names.- Returns:
- A new
NodeList
object containing all the matchedElements
. - Throws:
DOMException
- NOT_SUPPORTED_ERR: May be raised if the implementation does not support the feature"XML"
and the language exposed through the Document does not support XML Namespaces (such as [HTML 4.01]).- Since:
- 1.4, DOM Level 2
-
hasAttribute
Returnstrue
when an attribute with a given name is specified on this element or has a default value,false
otherwise.- Parameters:
name
- The name of the attribute to look for.- Returns:
true
if an attribute with the given name is specified on this element or has a default value,false
otherwise.- Since:
- 1.4, DOM Level 2
-
hasAttributeNS
Returnstrue
when an attribute with a given local name and namespace URI is specified on this element or has a default value,false
otherwise.
Per [XML Namespaces] , applications must use the valuenull
as thenamespaceURI
parameter for methods if they wish to have no namespace.- Parameters:
namespaceURI
- The namespace URI of the attribute to look for.localName
- The local name of the attribute to look for.- Returns:
true
if an attribute with the given local name and namespace URI is specified or has a default value on this element,false
otherwise.- Throws:
DOMException
- NOT_SUPPORTED_ERR: May be raised if the implementation does not support the feature"XML"
and the language exposed through the Document does not support XML Namespaces (such as [HTML 4.01]).- Since:
- 1.4, DOM Level 2
-
getSchemaTypeInfo
TypeInfo getSchemaTypeInfo()The type information associated with this element.- Since:
- 1.5, DOM Level 3
-
setIdAttribute
If the parameterisId
istrue
, this method declares the specified attribute to be a user-determined ID attribute . This affects the value ofAttr.isId
and the behavior ofDocument.getElementById
, but does not change any schema that may be in use, in particular this does not affect theAttr.schemaTypeInfo
of the specifiedAttr
node. Use the valuefalse
for the parameterisId
to undeclare an attribute for being a user-determined ID attribute.
To specify an attribute by local name and namespace URI, use thesetIdAttributeNS
method.- Parameters:
name
- The name of the attribute.isId
- Whether the attribute is a of type ID.- Throws:
DOMException
- NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly.
NOT_FOUND_ERR: Raised if the specified node is not an attribute of this element.- Since:
- 1.5, DOM Level 3
-
setIdAttributeNS
If the parameterisId
istrue
, this method declares the specified attribute to be a user-determined ID attribute . This affects the value ofAttr.isId
and the behavior ofDocument.getElementById
, but does not change any schema that may be in use, in particular this does not affect theAttr.schemaTypeInfo
of the specifiedAttr
node. Use the valuefalse
for the parameterisId
to undeclare an attribute for being a user-determined ID attribute.- Parameters:
namespaceURI
- The namespace URI of the attribute.localName
- The local name of the attribute.isId
- Whether the attribute is a of type ID.- Throws:
DOMException
- NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly.
NOT_FOUND_ERR: Raised if the specified node is not an attribute of this element.- Since:
- 1.5, DOM Level 3
-
setIdAttributeNode
If the parameterisId
istrue
, this method declares the specified attribute to be a user-determined ID attribute . This affects the value ofAttr.isId
and the behavior ofDocument.getElementById
, but does not change any schema that may be in use, in particular this does not affect theAttr.schemaTypeInfo
of the specifiedAttr
node. Use the valuefalse
for the parameterisId
to undeclare an attribute for being a user-determined ID attribute.- Parameters:
idAttr
- The attribute node.isId
- Whether the attribute is a of type ID.- Throws:
DOMException
- NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly.
NOT_FOUND_ERR: Raised if the specified node is not an attribute of this element.- Since:
- 1.5, DOM Level 3
-