sb.Append("Provider=Microsoft.Jet.OLEDB.4.0;");

            sb.Append("User ID=" + UID + ";Password=" + pwd);

   string connString = sb.ToString();

   conn.ConnectionString = connString;

   conn.Open();

   // Create the commands.

   string cmdString = "Insert into Orders"

      + " (OrderID, OrderDate, CustomerID)"

      + " values(''''ABC60'''', #4/14/04#, 456)";

   OleDbCommand cmdInsertOrder = new OleDbCommand(cmdString,conn);

   //No need to insert OrderLineID, as that is an AutoNumber field.

   cmdString = "Insert into OrderLines (OrderID, PartID, Quantity)"

      + " values(''''ABC60'''', 25, 10)";

   OleDbCommand cmdInsertOrderLine =

new OleDbCommand(cmdString,conn);

   cmdString = "Insert into PickList (OrderID, PartID, Quantity)"

      + " values(''''ABC60'''', 25, 10)";

   OleDbCommand cmdCreatePickList =

new OleDbCommand(cmdString,conn);

   // Begin the outer transaction and

   // enlist the order-related commands.

      OleDbTransaction tran = conn.BeginTransaction();

   cmdInsertOrder.Transaction = tran;

   cmdInsertOrderLine.Transaction = tran;

   try

   {

      // Execute the commands

      // to create the order and order

      // line items.

      cmdInsertOrder.ExecuteNonQuery();

      cmdInsertOrderLine.ExecuteNonQuery();

      // Create a nested transaction

      // that allows the pick list

      // creation to succeed or fail

      // separately if necessary.

      OleDbTransaction nestedTran = tran.Begin();

      // Enlist the pick list command.

      cmdCreatePickList.Transaction = nestedTran;

      try

      {

         // Execute the pick list command.

         cmdCreatePickList.ExecuteNonQuery();

         // Commit the nested transaction.

         nestedTran.Commit();

      }

      catch(OleDbException ex)

      {

         //Roll back the transaction.

         nestedTran.Rollback();

         // Add code to notify user or otherwise handle

         // the fact that the procedure was only

         // partially successful.

      }

      // Commit the outer transaction.

      tran.Commit();

   }

   catch(OleDbException ex)

   {

      //Roll back the transaction.

      tran.Rollback();

      //Additional error handling if needed.

   }

   finally

   {

      // Close the connection.

      conn.Close();

   }

}

注：　引擎提供者为Microsoft OLE DB，其支持内嵌事务．

总结

事务是一个强有力的方式，用来保证数据修改任务得到合适的处理，同时ado.net让我们处理数据存取的能力更容易．当你构建你的数据读取和使用方案的时候考虑到这些情况，你将会保证你数据的完整性．

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