--- title: Document.createTreeWalker() slug: Web/API/Document/createTreeWalker translation_of: Web/API/Document/createTreeWalker ---
{{ApiRef("Document")}}
Вызов метода Document.createTreeWalker() возвращает новый объект класса  {{domxref("TreeWalker")}}.

Синтаксис

document.createTreeWalker(root, whatToShow[, filter[, entityReferenceExpansion]]);

Параметры

root
корневой узел {{domxref("Node")}} для {{domxref("TreeWalker")}}. Чаще всего это элемент принадлежащий document.
whatToShow {{optional_inline}}
A unsigned long representing a bitmask created by combining the constant properties of NodeFilter. It is a convenient way of filtering for certain types of node. It defaults to 0xFFFFFFFF representing the SHOW_ALL constant.
Константа Числовое значение Описание
NodeFilter.SHOW_ALL -1 (that is the max value of unsigned long) Показывать все узлы.
NodeFilter.SHOW_ATTRIBUTE {{deprecated_inline}} 2 Shows attribute {{domxref("Attr")}} nodes. This is meaningful only when creating a {{domxref("TreeWalker")}} with an {{domxref("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 {{deprecated_inline}} 8 Shows {{domxref("CDATASection")}} nodes.
NodeFilter.SHOW_COMMENT 128 Shows {{domxref("Comment")}} nodes.
NodeFilter.SHOW_DOCUMENT 256 Shows {{domxref("Document")}} nodes.
NodeFilter.SHOW_DOCUMENT_FRAGMENT 1024 Shows {{domxref("DocumentFragment")}} nodes.
NodeFilter.SHOW_DOCUMENT_TYPE 512 Shows {{domxref("DocumentType")}} nodes.
NodeFilter.SHOW_ELEMENT 1 Shows {{domxref("Element")}} nodes.
NodeFilter.SHOW_ENTITY {{deprecated_inline}} 32 Shows {{domxref("Entity")}} nodes. This is meaningful only when creating a {{domxref("TreeWalker")}} with an {{domxref("Entity")}} node as its root; in this case, it means that the {{domxref("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 {{deprecated_inline}} 16 Shows {{domxref("EntityReference")}} nodes.
NodeFilter.SHOW_NOTATION {{deprecated_inline}} 2048 Shows {{domxref("Notation")}} nodes. This is meaningful only when creating a {{domxref("TreeWalker")}} with a {{domxref("Notation")}} node as its root; in this case, it means that the {{domxref("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 Shows {{domxref("ProcessingInstruction")}} nodes.
NodeFilter.SHOW_TEXT 4 Shows {{domxref("Text")}} nodes.
filter {{optional_inline}}
A {{domxref("NodeFilter")}}, that is an object with a method acceptNode, which is called by the {{domxref("TreeWalker")}} to determine whether or not to accept a node that has passed the whatToShow check.
entityReferenceExpansion {{optional_inline}} {{obsolete_inline}}
A {{domxref("Boolean")}} flag indicating if when discarding an {{domxref("EntityReference")}} its whole sub-tree must be discarded at the same time.

Return value

A new {{domxref("TreeWalker")}} object.

Example

The following example goes through all nodes in the body, reduces the set of nodes to elements, simply passes through as acceptable each node (it could reduce the set in the acceptNode() method instead), and then makes use of tree walker iterator that is created to advance through the nodes (now all elements) and push them into an array.

var treeWalker = document.createTreeWalker(
  document.body,
  NodeFilter.SHOW_ELEMENT,
  { acceptNode: function(node) { return NodeFilter.FILTER_ACCEPT; } },
  false
);

var nodeList = [];

while(treeWalker.nextNode()) nodeList.push(treeWalker.currentNode);

Specifications

Specification Status Comment
{{SpecName('DOM WHATWG', '#dom-document-createtreewalker', 'Document.createTreeWalker')}} {{Spec2('DOM WHATWG')}} Removed the expandEntityReferences parameter. Made the whatToShow and filter parameters optionals.
{{SpecName('DOM2 Traversal_Range', 'traversal.html#NodeIteratorFactory-createTreeWalker', 'Document.createTreeWalker')}} {{Spec2('DOM2 Traversal_Range')}} Initial definition

Browser compatibility

{{Compat("api.Document.createTreeWalker")}}

See also