multirow edit in Datagrid

[arun_mrk]

My web page has a datagrid(for multiple row edit) bind to a dataset with all the columns
been data bound except one which is a template column with a dropdownlist.
Users can only modify the dropdownlist.
Datagrid might have 1000 of rows of which the user is certainly going to modify DROPDOWN LIST value
for a few rows.
How can i identify the rows that are modified(best approach).
Could some suggest me some way(considering the speed issue also).

 

[Robby]

The HasChanges checks at the table level, it may (I doubt it) have one at the row level.