any one explain in detail........ ?

ASP.NET transaction support allows pages to participate in ongoing Microsoft .NET Framework transactions. Transaction support is exposed via an @Transaction directive that indicates the desired level of support: Required, RequiresNew, Supported, NotSupported, Disabled.
The Transaction attribute is applied at the class level too to indicate that all class methods should be run in the context of a transaction. If an unhandled exception is thrown during the execution of a class method, the transaction is aborted. Otherwise, the transaction is committed.
we can set the page level transaction by
<@page transaction='"required">
using System.EnterpriseServices;
[Transaction]
public class TransactionAttribute_Cl : ServicedComponent
{
}