TreeWalker: whatToShow property

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since ⁨July 2015⁩.

The TreeWalker.whatToShow read-only property returns a bitmask that indicates the types of nodes to show. Non-matching nodes are skipped, but their children may be included, if relevant.

Value

A non-negative integer. For the list of possible values, see document.createTreeWalker().

Examples

const treeWalker = document.createTreeWalker(
  document.body,
  NodeFilter.SHOW_ELEMENT + NodeFilter.SHOW_COMMENT + NodeFilter.SHOW_TEXT,
  { acceptNode: (node) => NodeFilter.FILTER_ACCEPT },
  false,
);
if (
  treeWalker.whatToShow === NodeFilter.SHOW_ALL ||
  treeWalker.whatToShow % (NodeFilter.SHOW_COMMENT * 2) >=
    NodeFilter.SHOW_COMMENT
) {
  // treeWalker will show comments
}