TreeWalker

Объект TreeWalker представляет узлы поддерева документа и позицию внутри них.

TreeWalker может быть создан с использованием метода Document.createTreeWalker()

Свойства

Этот интерфейс не наследует никакого свойства.

TreeWalker.root Только для чтения

Возвращает Node представляющий корневой узел, как указано когда TreeWalker был создан.

TreeWalker.whatToShow Только для чтения

Returns an unsigned long being a bitmask made of constants describing the types of Node that must be presented. Non-matching nodes are skipped, but their children may be included, if relevant. The possible values are:

Constant	Numerical value	Description
NodeFilter.SHOW_ALL	-1 (that is the max value of unsigned long)	Показывает все узлы.
NodeFilter.SHOW_ATTRIBUTE	2	Shows attribute Attr nodes. This is meaningful only when creating a TreeWalker with an Attr node as its root. In this case, it means that the attribute node will appear in the first position of the iteration or traversal. Since attributes are never children of other nodes, they do not appear when traversing over the document tree.
NodeFilter.SHOW_CDATA_SECTION	8	Показывает CDATASection узлы.
NodeFilter.SHOW_COMMENT	128	Показывает Comment узлы.
NodeFilter.SHOW_DOCUMENT	256	Показывает Document узлы.
NodeFilter.SHOW_DOCUMENT_FRAGMENT	1024	Показывает DocumentFragment узлы.
NodeFilter.SHOW_DOCUMENT_TYPE	512	Показывает DocumentType узлы.
NodeFilter.SHOW_ELEMENT	1	Показывает Element узлы.
NodeFilter.SHOW_ENTITY	32	Показывает Entity узлы. This is meaningful only when creating a TreeWalker with an Entity node as its root; in this case, it means that the Entity node will appear in the first position of the traversal. Since entities are not part of the document tree, they do not appear when traversing over the document tree.
NodeFilter.SHOW_ENTITY_REFERENCE	16	Показывает EntityReference узлы.
NodeFilter.SHOW_NOTATION	2048	Показывает Notation nodes. This is meaningful only when creating a TreeWalker with a Notation node as its root; in this case, it means that the Notation node will appear in the first position of the traversal. Since entities are not part of the document tree, they do not appear when traversing over the document tree.
NodeFilter.SHOW_PROCESSING_INSTRUCTION	64	Показывает ProcessingInstruction узлы.
NodeFilter.SHOW_TEXT	4	Shows Text узлы.

TreeWalker.filter Только для чтения

Возвращает NodeFilter используемый для выбора соответствующих узлов.

TreeWalker.expandEntityReferences Только для чтения

Is a Boolean indicating, when discarding an EntityReference its whole sub-tree must be discarded at the same time.

TreeWalker.currentNode

Is the Node on which the TreeWalker is currently pointing at.

Методы

Этот интерфейс не наследует никакого метода.

TreeWalker.parentNode()

Moves the current Node to the first visible ancestor node in the document order, and returns the found node. It also moves the current node to this one. If no such node exists, or if it is before that the root node defined at the object construction, returns null and the current node is not changed.

TreeWalker.firstChild()

Moves the current Node to the first visible child of the current node, and returns the found child. It also moves the current node to this child. If no such child exists, returns null and the current node is not changed.

TreeWalker.lastChild()

Moves the current Node to the last visible child of the current node, and returns the found child. It also moves the current node to this child. If no such child exists, null is returned and the current node is not changed.

TreeWalker.previousSibling()

Moves the current Node to its previous sibling, if any, and returns the found sibling. If there is no such node, return null and the current node is not changed.

TreeWalker.nextSibling()

Moves the current Node to its next sibling, if any, and returns the found sibling. If there is no such node, null is returned and the current node is not changed.

TreeWalker.previousNode()

Moves the current Node to the previous visible node in the document order, and returns the found node. It also moves the current node to this one. If no such node exists, or if it is before that the root node defined at the object construction, returns null and the current node is not changed.

TreeWalker.nextNode()

Moves the current Node to the next visible node in the document order, and returns the found node. It also moves the current node to this one. If no such node exists, returns null and the current node is not changed.

Спецификации

Совместимость с браузером

Смотрите также

• Метод создателя: Document.createTreeWalker().
• Связанные интерфейсы: NodeFilter, NodeIterator.