XML::DOM::Element(3) User Contributed Perl Documentation XML::DOM::Element(3)NAMEXML::DOM::Element - An XML element node in XML::DOM
DESCRIPTIONXML::DOM::Element extends XML::DOM::Node.
By far the vast majority of objects (apart from text) that authors
encounter when traversing a document are Element nodes. Assume the fol-
lowing XML document:
<elementExample id="demo">
<subelement1/>
<subelement2><subsubelement/></subelement2>
</elementExample>
When represented using DOM, the top node is an Element node for "ele-
mentExample", which contains two child Element nodes, one for "subele-
ment1" and one for "subelement2". "subelement1" contains no child
nodes.
Elements may have attributes associated with them; since the Element
interface inherits from Node, the generic Node interface method getAt-
tributes may be used to retrieve the set of all attributes for an ele-
ment. 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.
METHODS
getTagName
The name of the element. For example, in:
<elementExample id="demo">
...
</elementExample>
tagName has the value "elementExample". Note that this is case-pre-
serving in XML, as are all of the operations of the DOM.
getAttribute (name)
Retrieves an attribute value by name.
Return Value: The Attr value as a string, or the empty string if
that attribute does not have a specified or default value.
setAttribute (name, value)
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 refer-
ences, the user must create an Attr node plus any Text and Enti-
tyReference nodes, build the appropriate subtree, and use setAt-
tributeNode to assign it as the value of an attribute.
DOMExceptions:
* INVALID_CHARACTER_ERR
Raised if the specified name contains an invalid character.
* NO_MODIFICATION_ALLOWED_ERR
Raised if this node is readonly.
removeAttribute (name)
Removes an attribute by name. If the removed attribute has a
default value it is immediately replaced.
DOMExceptions:
* NO_MODIFICATION_ALLOWED_ERR
Raised if this node is readonly.
getAttributeNode
Retrieves an Attr node by name.
Return Value: The Attr node with the specified attribute name or
undef if there is no such attribute.
setAttributeNode (attr)
Adds a new attribute. If an attribute with that name is already
present in the element, it is replaced by the new one.
Return Value: If the newAttr attribute replaces an existing
attribute with the same name, the previously existing Attr node is
returned, otherwise undef is returned.
DOMExceptions:
* WRONG_DOCUMENT_ERR
Raised if newAttr 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 if newAttr is already an attribute of another Element
object. The DOM user must explicitly clone Attr nodes to re-use
them in other elements.
removeAttributeNode (oldAttr)
Removes the specified attribute. If the removed Attr has a default
value it is immediately replaced. If the Attr already is the
default value, nothing happens and nothing is returned.
Parameters:
oldAttr The Attr node to remove from the attribute list.
Return Value: The Attr node that was removed.
DOMExceptions:
* NO_MODIFICATION_ALLOWED_ERR
Raised if this node is readonly.
* NOT_FOUND_ERR
Raised if oldAttr is not an attribute of the element.
Additional methods not in the DOM Spec
setTagName (newTagName)
Sets the tag name of the Element. Note that this method is not
portable between DOM implementations.
DOMExceptions:
* INVALID_CHARACTER_ERR
Raised if the specified name contains an invalid character.
check ($checker)
Uses the specified XML::Checker to validate the document.
NOTE: an XML::Checker must be supplied. The checker can be cre-
ated in different ways, e.g. when parsing a document with
XML::DOM::ValParser, or with XML::DOM::Document::create-
Checker(). See XML::Checker for more info.
perl v5.8.8 2002-02-09 XML::DOM::Element(3)
