for (int r = 2; r <= ws.UsedRange.Rows.Count; r++)
    {    if (ws.UsedRange.Cells[r, 3].Text == "0")
            {
                DataRow row = dt.NewRow();

                for (int c = 1; c < ws.UsedRange.Columns.Count; c++)
            {
                string cell = ws.Cells[r, c].Text;
                row[c - 1] = cell;
          }
     }