c# excel 2 dataset

private string InsertSql(string XlsFileName)
    {
        string err = "";
        DataSet ds = new DataSet();
        OleDbConnection con = new OleDbConnection("Provider=Microsoft.jet.OLEDB.4.0;Data Source=" + XlsFileName + ";Extended Properties='Excel 8.0;HDR=Yes;IMEX=1;'");

        con.Open();
        string sql = "select * from [Sheet1$]";
        OleDbCommand cmd = new OleDbCommand(sql, con);
        OleDbDataAdapter adp = new OleDbDataAdapter(cmd);
        adp.Fill(ds, "clbm");
        con.Close();
        for (int i = 0; i < ds.Tables["clbm"].Rows.Count; i++)
        {            
            string cr_id = ds.Tables["clbm"].Rows[i][0].ToString();
            string tongid = ds.Tables["clbm"].Rows[i][1].ToString();
            if (!string.IsNullOrEmpty(cr_id) && !string.IsNullOrEmpty(tongid))
            {
                if (!Import(tongid, cr_id))
                {
                    err += cr_id + "，";
                }
            }
        }
        return err == "" ? "导入成功！" : "导入发生错误的需求编码：" + err;
    }

 

    }