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. |
Inherits from |
Node |
Default Constructor |
Element(GdomeElement* = 0) |
Creates a smart pointer for the Gdome element whose pointer is passed as an argument. The user should never pass a non-null pointer to this constructor. |
Copy and Cast Constructors |
Element(const
Element&)
Element(const Node&) |
These constructors can be used to copy a smart pointer or to downcast it. If the downcasting is not possible, the resulting smart pointer will be null. |
Copy Operator |
Element& operator=(const Element&) |
Equality |
bool operator==(const
Element&) const
bool operator!=(const Element&) const |
Two smart pointers are equal if they point to the same Gdome object. |
Attributes |
DOMString get_tagName(void) const |
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. The HTML DOM returns the tagName of an HTML element in the canonical uppercase form, regardless of the case in the source HTML document. |
Methods |
DOMString getAttribute(const DOMString& name) |
Parameters:
Retrieves an attribute value by name. |
void setAttribute(const DOMString& name, const DOMString& value) |
Parameters:
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. To set an attribute with a qualified name and namespace URI, use the setAttributeNS method. Exceptions:
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void removeAttribute(const DOMString& name) |
Parameters:
Removes an attribute by name. If the removed attribute is known to have a default value, an attribute immediately appears containing the default value as well as the corresponding namespace URI, local name, and prefix when applicable. To remove an attribute by local name and namespace URI, use the removeAttributeNS method. Exceptions:
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Attr getAttributeNode(const DOMString& name) |
Parameters:
Retrieves an attribute node by name. To retrieve an attribute node by qualified name and namespace URI, use the getAttributeNodeNS method. |
Attr setAttributeNode(const Attr& newAttr) |
Parameters:
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. To add a new attribute node with a qualified name and namespace URI, use the setAttributeNodeNS method. Exceptions:
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Attr removeAttributeNode(const Attr& oldAttr) |
Parameters:
Removes the specified attribute node. If the removed Attr has a default value it is immediately replaced. The replacing attribute has the same namespace URI and local name, as well as the original prefix, when applicable. Exceptions:
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NodeList getElementsByTagName(const DOMString& name) |
Parameters:
Returns a NodeList of all descendant Elements with a given tag name, in the order in which they are encountered in a preorder traversal of this Element tree. |
DOMString getAttributeNS(const DOMString& namespaceURI, const DOMString& localName) |
Parameters:
Retrieves an attribute value by local name and namespace URI. HTML-only DOM implementations do not need to implement this method. |
void setAttributeNS(const DOMString& namespaceURI, const DOMString& qualifiedName, const DOMString& value) |
Parameters:
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 the qualifiedName, and its value is changed to be 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 setAttributeNodeNS or setAttributeNode to assign it as the value of an attribute. HTML-only DOM implementations do not need to implement this method. Exceptions:
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void removeAttributeNS(const DOMString& namespaceURI, const DOMString& localName) |
Parameters:
Removes an attribute by local name and namespace URI. If the removed attribute has a default value it is immediately replaced. The replacing attribute has the same namespace URI and local name, as well as the original prefix. HTML-only DOM implementations do not need to implement this method. Exceptions:
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Attr getAttributeNodeNS(const DOMString& namespaceURI, const DOMString& localName) |
Parameters:
Retrieves an Attr node by local name and namespace URI. HTML-only DOM implementations do not need to implement this method. |
Attr setAttributeNodeNS(const Attr& newAttr) |
Parameters:
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. HTML-only DOM implementations do not need to implement this method. Exceptions:
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NodeList getElementsByTagNameNS(const DOMString& namespaceURI, const DOMString& localName) |
Parameters:
Returns a NodeList of all the descendant Elements with a given local name and namespace URI in the order in which they are encountered in a preorder traversal of this Element tree. HTML-only DOM implementations do not need to implement this method. |
bool hasAttribute(const DOMString& name) |
Parameters:
Returns true when an attribute with a given name is specified on this element or has a default value, false otherwise. |
bool hasAttributeNS(const DOMString& namespaceURI, const DOMString& localName) |
Parameters:
Returns true when an attribute with a given local name and namespace URI is specified on this element or has a default value, false otherwise. HTML-only DOM implementations do not need to implement this method. |