/// <summary>
        /// 读取Excel文件，将内容存储在DataSet中
        /// </summary>
        /// <param name="opnFileName">带路径的Excel文件名</param>
        /// <returns>DataSet</returns>
        private DataSet ExcelToDataSet(string opnFileName)
        {
            string strConn = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source="+opnFileName+";Extended Properties=\"Excel 8.0;HDR=YES;IMEX=1\"";
            OleDbConnection conn = new OleDbConnection(strConn);            
            string strExcel = "";
            OleDbDataAdapter myCommand = null;
            DataSet ds = new DataSet();
            strExcel = "select * from [sheet1$]";
            try
            {
                conn.Open();
                myCommand = new OleDbDataAdapter(strExcel, strConn);
                myCommand.Fill(ds,"dtSource");
                return ds;
            }
            catch (Exception ex)
            {
                MessageBox.Show("导入出错：" + ex, "错误信息");
                return ds;
            }
            finally
            {
                conn.Close();
                conn.Dispose();
            }
        }