--- title: Document.createTreeWalker() slug: Web/API/Document/createTreeWalker translation_of: Web/API/Document/createTreeWalker ---
Document.createTreeWalker()
возвращает новый объект класса {{domxref("TreeWalker")}}.document.createTreeWalker(root, whatToShow[, filter[, entityReferenceExpansion]]);
root
whatToShow
{{optional_inline}}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}}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 new {{domxref("TreeWalker")}} object.
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);
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 |
{{Compat("api.Document.createTreeWalker")}}