1XML::DOM::Element(3)  User Contributed Perl Documentation XML::DOM::Element(3)
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NAME

6       XML::DOM::Element - An XML element node in XML::DOM
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DESCRIPTION

9       XML::DOM::Element extends XML::DOM::Node.
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11       By far the vast majority of objects (apart from text) that authors
12       encounter when traversing a document are Element nodes. Assume the
13       following XML document:
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15            <elementExample id="demo">
16              <subelement1/>
17              <subelement2><subsubelement/></subelement2>
18            </elementExample>
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20       When represented using DOM, the top node is an Element node for
21       "elementExample", which contains two child Element nodes, one for
22       "subelement1" and one for "subelement2". "subelement1" contains no
23       child nodes.
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25       Elements may have attributes associated with them; since the Element
26       interface inherits from Node, the generic Node interface method
27       getAttributes may be used to retrieve the set of all attributes for an
28       element. There are methods on the Element interface to retrieve either
29       an Attr object by name or an attribute value by name. In XML, where an
30       attribute value may contain entity references, an Attr object should be
31       retrieved to examine the possibly fairly complex sub-tree representing
32       the attribute value. On the other hand, in HTML, where all attributes
33       have simple string values, methods to directly access an attribute
34       value can safely be used as a convenience.
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36   METHODS
37       getTagName
38           The name of the element. For example, in:
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40                          <elementExample id="demo">
41                                  ...
42                          </elementExample>
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44           tagName has the value "elementExample". Note that this is case-
45           preserving in XML, as are all of the operations of the DOM.
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47       getAttribute (name)
48           Retrieves an attribute value by name.
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50           Return Value: The Attr value as a string, or the empty string if
51           that attribute does not have a specified or default value.
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53       setAttribute (name, value)
54           Adds a new attribute. If an attribute with that name is already
55           present in the element, its value is changed to be that of the
56           value parameter. This value is a simple string, it is not parsed as
57           it is being set. So any markup (such as syntax to be recognized as
58           an entity reference) is treated as literal text, and needs to be
59           appropriately escaped by the implementation when it is written out.
60           In order to assign an attribute value that contains entity
61           references, the user must create an Attr node plus any Text and
62           EntityReference nodes, build the appropriate subtree, and use
63           setAttributeNode to assign it as the value of an attribute.
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65           DOMExceptions:
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67           •   INVALID_CHARACTER_ERR
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69               Raised if the specified name contains an invalid character.
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71           •   NO_MODIFICATION_ALLOWED_ERR
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73               Raised if this node is readonly.
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75       removeAttribute (name)
76           Removes an attribute by name. If the removed attribute has a
77           default value it is immediately replaced.
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79           DOMExceptions:
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81           •   NO_MODIFICATION_ALLOWED_ERR
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83               Raised if this node is readonly.
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85       getAttributeNode
86           Retrieves an Attr node by name.
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88           Return Value: The Attr node with the specified attribute name or
89           undef if there is no such attribute.
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91       setAttributeNode (attr)
92           Adds a new attribute. If an attribute with that name is already
93           present in the element, it is replaced by the new one.
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95           Return Value: If the newAttr attribute replaces an existing
96           attribute with the same name, the previously existing Attr node is
97           returned, otherwise undef is returned.
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99           DOMExceptions:
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101           •   WRONG_DOCUMENT_ERR
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103               Raised if newAttr was created from a different document than
104               the one that created the element.
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106           •   NO_MODIFICATION_ALLOWED_ERR
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108               Raised if this node is readonly.
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110           •   INUSE_ATTRIBUTE_ERR
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112               Raised if newAttr is already an attribute of another Element
113               object. The DOM user must explicitly clone Attr nodes to re-use
114               them in other elements.
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116       removeAttributeNode (oldAttr)
117           Removes the specified attribute. If the removed Attr has a default
118           value it is immediately replaced. If the Attr already is the
119           default value, nothing happens and nothing is returned.
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121           Parameters:
122            oldAttr  The Attr node to remove from the attribute list.
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124           Return Value: The Attr node that was removed.
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126           DOMExceptions:
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128           •   NO_MODIFICATION_ALLOWED_ERR
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130               Raised if this node is readonly.
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132           •   NOT_FOUND_ERR
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134               Raised if oldAttr is not an attribute of the element.
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136   Additional methods not in the DOM Spec
137       setTagName (newTagName)
138           Sets the tag name of the Element. Note that this method is not
139           portable between DOM implementations.
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141           DOMExceptions:
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143           •   INVALID_CHARACTER_ERR
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145               Raised if the specified name contains an invalid character.
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147       check ($checker)
148           Uses the specified XML::Checker to validate the document.  NOTE: an
149           XML::Checker must be supplied. The checker can be created in
150           different ways, e.g. when parsing a document with
151           XML::DOM::ValParser, or with XML::DOM::Document::createChecker().
152           See XML::Checker for more info.
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156perl v5.34.0                      2022-01-21              XML::DOM::Element(3)