XML::DOM::Element - An XML element node in XML::DOM
XML::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 following
XML document:
<elementExample id="demo">
<subelement1/>
<subelement2><subsubelement/></subelement2>
</elementExample>
When represented using DOM, the top node is an Element node for
"elementExample", which contains two child Element nodes, one for
"subelement1" 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
getAttributes 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.
- getTagName
- The name of the element. 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.
- 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 references, the user must create an Attr node
plus any Text and EntityReference nodes, build the appropriate subtree,
and use setAttributeNode to assign it as the value of an attribute.
DOMExceptions:
- 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:
- 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 created in different
ways, e.g. when parsing a document with XML::DOM::ValParser, or with
XML::DOM::Document::createChecker(). See XML::Checker for more
info.
Hey! The above document had some coding errors, which are explained
below:
- Around line 162:
- You forgot a '=back' before '=head2'