How to Efficiently Get All TextNode Objects in a Document?

Get Collection of TextNode Objects

While getElementsByTagName() efficiently retrieves element objects, it's ineffective for textNode objects as they aren't elements. Hence, the question arises: is there an alternative method to acquire all textNode objects within a document?

Alternative Methods

Although walking the DOM is a viable option, the lack of a browser-native approach seems peculiar. To address this, several methods have emerged:

1. TreeWalker: A dedicated tool for traversing the DOM, it efficiently identifies text nodes.
2. Custom Iterative Traversal: A manual method that traverses the DOM, checking each node's type and gathering text nodes.
3. Custom Recursive Traversal: Similar to the iterative method but utilizes recursion for DOM traversal.
4. Xpath query: A language-based approach that can select text nodes based on specified criteria.
5. querySelectorAll: A modernized method that allows the selection of text nodes using complex selectors.
6. getElementsByTagName: A flawed but interesting method that assumes the first child of an element is a text element, despite being designed for elements.

Performance Comparison

Performance tests have been conducted over 1000 runs to compare these methods. While getElementsByTagName stands out as the fastest, it resorts to selecting specific element tags and might not capture all text nodes.

Interestingly, TreeWalker performs nearly identically to getElementsByTagName and is arguably comparable in speed to the more elaborate DOM traversing methods. This highlights the efficiency of TreeWalker for retrieving text nodes.

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