从Excel转Access的一个方法说开去（DataRow的state状态）

  /// <summary>
        /// 
        /// </summary>
        /// <param name="excelpath">excel路径</param>
        /// <param name="exceltablename">Excel表名</param>
        /// <param name="accessmodelpath">access模版路径</param>
        /// <param name="accesspath">access输出路径</param>
        ///  <param name="accesstablename">access表名</param>
        /// <param name="msg">错误信息</param>
        /// <returns></returns>
        public static bool ExcelToAccess(string excelpath, string exceltablename, string accessmodelpath, string accesspath, string accesstablename, ref string msg)
        {

            try
            {
                DataTable dt = ExcelToDataTable(excelpath, exceltablename);
                if (dt == null)
                {
                    msg = "Excel没有任何内容";
                    return false;
                }
                accesspath = accesspath + "\\生成的access.mdb";
                System.IO.File.Copy(accessmodelpath, accesspath, true);
                string connStr = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + accesspath + ";User Id=admin;Password=;";
                string sql = "Select * from " + accesstablename + "";
                System.Data.OleDb.OleDbConnection conn = new System.Data.OleDb.OleDbConnection(connStr);
                System.Data.OleDb.OleDbDataAdapter da = new System.Data.OleDb.OleDbDataAdapter(sql, conn);
                System.Data.DataTable acedt = new DataTable();
           
                da.Fill(acedt);

                System.Data.OleDb.OleDbCommandBuilder ocb = new System.Data.OleDb.OleDbCommandBuilder(da);
                da.InsertCommand = ocb.GetInsertCommand();
                DataRow[] drs = dt.Select();
                foreach (DataRow r in drs)
                {
                    acedt.ImportRow(r);
                }
               // acedt.AcceptChanges();//此处不能有
                da.Update(acedt);
              
                da.Dispose();
                conn.Close();
                conn.Dispose();
                return true;
            }
            catch (Exception ex)
            {
                msg = ex.Message;
                return false;
            }
        }

    /// <summary>
        /// Excel转换成datatable
        /// </summary>
        /// <param name="excelpath"></param>
        /// <param name="exceltablename"></param>
        /// <returns></returns>
        public static DataTable ExcelToDataTable(string excelpath, string exceltablename)
        {
            try
            {
                //

                string strCon =string.Format(  "Provider=Microsoft.Jet.OLEDB.4.0;Data Source={0};Extended Properties=‘Excel 8.0;IMEX=1‘",excelpath);
                OleDbConnection Conn = new OleDbConnection(strCon);
                string strCom = "SELECT distinct  * FROM [" + exceltablename + "$]  where 1=1 ";
                OleDbDataAdapter da = new OleDbDataAdapter(strCom, Conn);
                DataTable dt = new DataTable();
                da.AcceptChangesDuringFill = false;
                da.Fill(dt);
                return dt;
            }
            catch(Exception ex)
            {
                return null;
            }
        }

  static void Main(string[] args)
        {
            // Run a function to create a DataTable with one column.
            DataTable table = MakeTable();
            DataRow row;

            // Create a new DataRow.
            row = table.NewRow();
            // Detached row.
            Console.WriteLine("New Row " + row.RowState);

            table.Rows.Add(row);
            // New row.
            Console.WriteLine("AddRow " + row.RowState);

            table.AcceptChanges();
            // Unchanged row.
            Console.WriteLine("AcceptChanges " + row.RowState);

            row["FirstName"] = "Scott";
            // Modified row.
            Console.WriteLine("Modified " + row.RowState);

            row.Delete();
            // Deleted row.
            Console.WriteLine("Deleted " + row.RowState);

    
            Console.ReadKey();
        }
        private static  DataTable MakeTable()
        {
            // Make a simple table with one column.
            DataTable table = new DataTable("table");
            DataColumn dcFirstName = new DataColumn(
                "FirstName", Type.GetType("System.String"));
            table.Columns.Add(dcFirstName);
            return table;
        }