Method: Document.createTreeWalker()

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The createTreeWalker() method creates a TreeWalker object, which you can use to traverse the specified document subtree.

Document.createTreeWalker( root, whatToShow, filter, expandEntityReference )

Parameter	Type	Description
`root`	`Node`	The node that will serve as the root for this `TreeWalker` object. The `TreeWalker.currentNode` property is set to the value of `root`.
`whatToShow`	unsigned long	The types of nodes to show in the tree view. The value may be one or more of: `0xFFFFFFFF` = `SHOW_ALL` `0x00000001` = `SHOW_ELEMENT` `0x00000002` = `SHOW_ATTRIBUTE` `0x00000004` = `SHOW_TEXT` `0x00000008` = `SHOW_CDATA_SECTION` `0x00000010` = `SHOW_ENTITY_REFERENCE` `0x00000020` = `SHOW_ENTITY` `0x00000040` = `SHOW_PROCESSING_INSTRUCTION` `0x00000080` = `SHOW_COMMENT` `0x00000100` = `SHOW_DOCUMENT` `0x00000200` = `SHOW_DOCUMENT_TYPE` `0x00000400` = `SHOW_DOCUMENT_FRAGMENT` `0x00000800` = `SHOW_NOTATION` Multiple values may be specified using a bitwise OR. Note that because attributes, entities, and notations are not the child of any other node, they never appear in the `TreeWalker` object’s logical view unless root is defined as a `Node` of that type. If the respective object is not defined as the root, then `SHOW_ATTRIBUTE`, `SHOW_ENTITY`, and `SHOW_NOTATION` have no meaning.
`filter`	`NodeFilter`	The filter to use with this `TreeWalker` object. This parameter may be null.
`entityReferenceExpansion`	boolean	When `true`, this method specifies that entity reference nodes should be expanded.

Returns the new TreeWalker object.

Exception	Description
`NOT_SUPPORTED_ERR`	This error is thrown if the specified root is null.