One way is to create backup DOMs (i.e. use the clone(true) method) and then when the users click Reset, then do a replaceChild() to restore the backup DOMs.

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Greg Collins [InfoPath MVP]
Please visit: http://www.InfoPathDev.com
Hi,
I need to create a button (a few buttons) that will reset all data sources
in a particular section to the default value. I'm using VBscript as I'm more
familiar with this. I don't know how to do this at all.
Thanks very much,
Charlie