Programming WCF Services

The Transaction Class

The Transaction class from the System.Transactions namespace, introduced in .NET 2.0, represents the transaction all WCF transaction managers work with:

[Serializable]
public class Transaction : IDisposable,ISerializable
{
   public static TransactionCurrent
   {get;set;}

   public void Rollback( ); //Abort the transaction
   public void Dispose( );

   //More members
}

Developers rarely need to interact with the Transaction class directly. The main use of the Transaction class is to manually abort the transaction by calling the Rollback( ) method. Additional features of the Transaction class include enlisting resource managers, setting the isolation level, subscribing to transaction events, cloning the transaction for concurrent threads, and obtaining transaction status and information.

The Ambient Transaction

.NET 2.0 defines a concept called an ambient transaction. The ambient transaction is the transaction in which your code executes. To obtain a reference to the ambient transaction, call the static Current property of Transaction:

Transaction ambientTransaction = Transaction.Current;

If there is no ambient transaction, Current will return null. Every piece of code, be it client or service, can always reach out for its ambient transaction. The ambient transaction object is stored in the thread local storage (TLS). As a result, when the thread winds its way across multiple objects and methods on the same call chain, all objects and methods can access their ambient transactions. ...