int rowcount_temp = dt.Rows.Count;
for (int i=0; i <rowcount_temp; i++)
{
Button btnDetails = sender as Button;
GridViewRow row = (GridViewRow)btnDetails.NamingContainer;
int id = int.Parse(this.GridView1.DataKeys[row.RowIndex].Value.ToString());
string Temp = row.Cells[i].Text;
}