foreach(gridviewrow gvr in Gridview1.Rows)
{
lstGridColumn.add(gvr.Cells[2].Text);
}
where lstGridColumn is a
List<string></string>
type. You need to iterate through each rows in the grid and extract the value from each Column specified by Cells[2] in the code.
This is used for asp.net websites and webapplications, if it is a windows form application then you'll probably need the row index of the datagrid to work with.
Other than that we need more info on your problem...please elaborate.