DOM Traversal: NodeIterator or TreeWalker?

I posted this question in a moribund group but now post it here:

I have an HTML document with a TABLE element and I want to count the number
of rows, presumably counting TR elements taking into account 'rowspan'
attributes; and the number of columns, presumably counting TH and TD
elements taking into 'colspan' attributes.

I have my own old code (probably bug-ridden) and would rather use the
Traversal DOM.

What is the best to use, a NodeInterator or TreeWalker? The use of the
NodeFilter is a bit confusing. If you have any advice I should consider
when I write this code, thanks.

I want this to work with MSIE too, and I usually write those DOM functions
as best as possible when MSIE has not implemented it. Has MS implemented
it?



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