After selecting an item to edit in a listview, what happens between each cycle of the onItemDataBound event an how do you debug it?

For some reason, I get an error half way through cycling through my items in a listview right before a record that has a null value for one of its items.  It doesnt' haappen any other time.  It happens after completing one cycle of the onItemDatabound event for a record in a row that is immediately before a particular null value in record immediatley following.
My code is written to look for the proper edititemindex, and if it sees it, then it checks for null values for all the items.  I can't even get that far, it errors just before the onItemDatabound even runs for the correc edit index.
Any ideas?
 
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