C# 4 and .NET 4

system.Transactions ❘ 617
tx.Complete();
}
Utilities.DisplayTransactionInformation("Dependent TX Complete",
tx.TransactionInformation);
code snippet TransactionSamples/Program.cs
With the DependentTransaction() method, fi rst a root transaction is created by instantiating
the class CommittableTransaction , and the transaction information is shown. Next, the method
tx.DependentClone() creates a dependent transaction. This dependent transaction is passed to the
method TxThread() that is defi ned as the entry point of a new thread.
The method DependentClone() requires an argument of type DependentCloneOption , which
is an enumeration with the values BlockCommitUntilComplete and RollbackIfNotComplete .
This option is important if the root transaction completes before the dependent transaction. Setting the
option to RollbackIfNotComplete , the transaction aborts if the dependent transaction didn ’ t invoke
the Complete() method before the Commit() method of the root transaction. Setting the option to
BlockCommitUntilComplete , the method Commit() waits until the outcome is defi ned by all dependent
transactions.
Next, the Commit() method of the CommittableTransaction class is invoked if the user does not abort the
transaction.
Chapter 20, “Threads, Tasks, and Synchronization,” covers threading.
static void DependentTransaction()
{
var tx = new CommittableTransaction();
Utilities.DisplayTransactionInformation("Root TX created",
tx.TransactionInformation);
try
{
new Thread(TxThread).Start(tx.DependentClone(
DependentCloneOption.BlockCommitUntilComplete));
if (Utilities.AbortTx())
{
throw new ApplicationException("transaction abort");
}
tx.Commit();
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
tx.Rollback();
}
}
Utilities.DisplayTransactionInformation("TX finished",
tx.TransactionInformation);
code snippet TransactionSamples/Program.cs
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