string filePath = Setting.SourcePath ;
            string sheetName = Setting.SourceFile;
            string strConn = "";

            strConn = (@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + filePath + ";Extended Properties=Text");

            if (!this.isOpened)
              myOleDbConnection = new OleDbConnection(strConn);

            try
            {
                myOleDbConnection.Open();

                isOpened = true;
                //get all sheets
                //DataTable dataTable = myOleDbConnection.GetOleDbSchemaTable(System.Data.OleDb.OleDbSchemaGuid.Tables, null);

                //foreach (System.Data.DataRow drow in dataTable.Rows)
                //{
                //    sheetName = drow["Table_Name"].ToString();
                //    DataTable tableColumns = myOleDbConnection.GetOleDbSchemaTable(OleDbSchemaGuid.Columns, new object[] { null, null, sheetName, null });
                //    break;
                //}
               
                OleDbCommand myOleDbCommand = new OleDbCommand("SELECT * FROM " + sheetName, myOleDbConnection);
                dataReader = myOleDbCommand.ExecuteReader();