13.6.2.2 Node Objects

Python 2.2

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13.6.2.2 Node Objects

All of the components of an XML document are subclasses of Node.

nodeType: An integer representing the node type. Symbolic constants for the types are on the Node object: ELEMENT_NODE, ATTRIBUTE_NODE, TEXT_NODE, CDATA_SECTION_NODE, ENTITY_NODE, PROCESSING_INSTRUCTION_NODE, COMMENT_NODE, DOCUMENT_NODE, DOCUMENT_TYPE_NODE, NOTATION_NODE. This is a read-only attribute.

parentNode: The parent of the current node, or None for the document node. The value is always a Node object or None. For Element nodes, this will be the parent element, except for the root element, in which case it will be the Document object. For Attr nodes, this is always None. This is a read-only attribute.

attributes: A NamedNodeMap of attribute objects. Only elements have actual values for this; others provide None for this attribute. This is a read-only attribute.

previousSibling: The node that immediately precedes this one with the same parent. For instance the element with an end-tag that comes just before the self element's start-tag. Of course, XML documents are made up of more than just elements so the previous sibling could be text, a comment, or something else. If this node is the first child of the parent, this attribute will be None. This is a read-only attribute.

nextSibling: The node that immediately follows this one with the same parent. See also previousSibling. If this is the last child of the parent, this attribute will be None. This is a read-only attribute.

childNodes: A list of nodes contained within this node. This is a read-only attribute.

firstChild: The first child of the node, if there are any, or None. This is a read-only attribute.

lastChild: The last child of the node, if there are any, or None. This is a read-only attribute.

localName: The part of the tagName following the colon if there is one, else the entire tagName. The value is a string.

prefix: The part of the tagName preceding the colon if there is one, else the empty string. The value is a string, or None

namespaceURI: The namespace associated with the element name. This will be a string or None. This is a read-only attribute.

nodeName: This has a different meaning for each node type; see the DOM specification for details. You can always get the information you would get here from another property such as the tagName property for elements or the name property for attributes. For all node types, the value of this attribute will be either a string or None. This is a read-only attribute.

nodeValue: This has a different meaning for each node type; see the DOM specification for details. The situation is similar to that with nodeName. The value is a string or None.

hasAttributes( ): Returns true if the node has any attributes.

hasChildNodes( ): Returns true if the node has any child nodes.

isSameNode( other)

Returns true if other refers to the same node as this node. This is especially useful for DOM implementations which use any sort of proxy architecture (because more than one object can refer to the same node).

Note: This is based on a proposed DOM Level 3 API which is still in the ``working draft'' stage, but this particular interface appears uncontroversial. Changes from the W3C will not necessarily affect this method in the Python DOM interface (though any new W3C API for this would also be supported).

appendChild( newChild): Add a new child node to this node at the end of the list of children, returning newChild.

insertBefore( newChild, refChild): Insert a new child node before an existing child. It must be the case that refChild is a child of this node; if not, ValueError is raised. newChild is returned. If refChild is None, it inserts newChild at the end of the children's list.

removeChild( oldChild): Remove a child node. oldChild must be a child of this node; if not, ValueError is raised. oldChild is returned on success. If oldChild will not be used further, its unlink() method should be called.

replaceChild( newChild, oldChild): Replace an existing node with a new node. It must be the case that oldChild is a child of this node; if not, ValueError is raised.

normalize( ): Join adjacent text nodes so that all stretches of text are stored as single Text instances. This simplifies processing text from a DOM tree for many applications. New in version 2.1.

cloneNode( deep): Clone this node. Setting deep means to clone all child nodes as well. This returns the clone.

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