how can i get the gridview column reference

Question

hi,
this is koti i have small need of gridview that is when i am click the edit button on the row some number of feilds(columns) are in non editing mode based on condition and i chage that editable ness dynamically according to my needs is it possible ?
ex: in a attendence grdivew tha user can not edit the privious 2 days(coloumns) for all records  remaining all days( columns )are in edit mode if not possibel
tell how can we get the reference of the feildsd in the gridview