How Can I Efficiently Retrieve All Text Nodes in a Document, Given the Limitations of `getElementsByTagName()`?

getElementsByTagName() Equivalent for TextNodes

While getElementsByTagName() efficiently retrieves collections of elements within a document, it excludes textNode objects, posing a unique challenge.

Alternative Approaches

Despite the absence of a native method to obtain all textNode objects, several approaches can effectively achieve this:

1. TreeWalker:
Utilizes a TreeWalker to navigate the DOM in a depth-first manner, identifying and collecting textNodes.

2. Custom Traversal Iterative:
Iteratively traverses the DOM, examining each node and categorizing any node type 3 as a textNode.

3. Custom Traversal Recursive:
Employs a recursive function to descend through the DOM, capturing textNodes encountered along the traversal path.

4. Xpath Query:
Leverages an XPath expression to select all textNodes within the document.

5. querySelectorAll:
Selects all nodes within the DOM and filters the result to include only textNodes.

6. getElementsByTagName (Handicap):
Attempts to identify textNodes indirectly by targeting the first child of every element retrieved by getElementsByTagName(), assuming it to be a textNode. Note that this approach has limitations and should be used with caution.

Performance Comparison

Performance testing reveals that getElementsByTagName() performs fastest but excludes certain textNodes. In contrast, TreeWalker exhibits comparable speed while capturing all textNodes effectively. The custom recursive traversal method is the slowest of the methods tested.

Additional Considerations

Irrespective of the chosen method, accessing the actual text content of textNodes requires subsequent iteration and extraction using node.nodeValue.
For further insights, refer to the discussion at http://bytes.com/topic/javascript/answers/153239-how-do-i-get-elements-text-node.

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