GridView: get selected rows

Below is sample C# code to get selected rows in GridView.

        protected int[] GetSelectedRows()
        {
            List rowIDs = new List();
            foreach (GridViewRow row in GridView.Rows)
            {
                CheckBox cb = ((CheckBox)row.FindControl("chkRow"));
                if (cb.Checked)
                {
                    string IDString = GridView.DataKeys[row.RowIndex].Value.ToString();
                    rowIDs.Add(Int32.Parse(IDString));
                }
            }
            return rowIDs.ToArray();
        }