OpenFileDialog openFD = new OpenFileDialog();

            openFD.FileName = "";

            openFD.Filter = "xls|*.xls|xlsx|*.xlsx";

            openFD.Title = "选择更新文件";

            openFD.Multiselect = false;

            if (openFD.ShowDialog() == DialogResult.OK)

            {

                this.tbSelectFile.Text = openFD.FileName;

                //读取Excel

                pDataSet.Clear();
//成功的关键在于下面这句话，网上有很多不同版本，但这个是亲测可用的。

                string strConn = "Provider=Microsoft.Ace.OLEDB.12.0;Data Source=" + openFD .FileName  + ";" + "Extended Properties=Excel 8.0;";

                OleDbConnection conn = new OleDbConnection(strConn);

                conn.Open();

                string strExcel = "";

                OleDbDataAdapter myCommand = null;

                strExcel = "select * from [sheet1$]";

                myCommand = new OleDbDataAdapter(strExcel, strConn);

                myCommand.Fill(pDataSet , "table1");

                conn.Close();

}