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DependentCloneOption Enum

Definition

Controls what kind of dependent transaction to create.

public enum class DependentCloneOption
public enum DependentCloneOption
type DependentCloneOption = 
Public Enum DependentCloneOption
Inheritance
DependentCloneOption

Fields

Name Value Description
BlockCommitUntilComplete 0

The dependent transaction blocks the commit process of the transaction until the parent transaction times out, or Complete() is called. In this case, additional work can be done on the transaction and new enlistments can be created.

RollbackIfNotComplete 1

The dependent transaction automatically aborts the transaction if Commit is called on the parent transaction before Complete() is called.

Examples

The following example shows you how to create a dependent transaction.

static void Main(string[] args)
{
    try
    {
        using (TransactionScope scope = new TransactionScope())
        {
            // Perform transactional work here.

            //Queue work item
            ThreadPool.QueueUserWorkItem(new WaitCallback(WorkerThread), Transaction.Current.DependentClone(DependentCloneOption.BlockCommitUntilComplete));

            //Display transaction information
            Console.WriteLine("Transaction information:");
            Console.WriteLine("ID:             {0}", Transaction.Current.TransactionInformation.LocalIdentifier);
            Console.WriteLine("status:         {0}", Transaction.Current.TransactionInformation.Status);
            Console.WriteLine("isolationlevel: {0}", Transaction.Current.IsolationLevel);

            //Call Complete on the TransactionScope based on console input
            ConsoleKeyInfo c;
            while (true)
            {
                            Console.Write("Complete the transaction scope? [Y|N] ");
                c = Console.ReadKey();
                Console.WriteLine();

                if ((c.KeyChar == 'Y') || (c.KeyChar == 'y'))
                {
                    //Call complete on the scope
                    scope.Complete();
                    break;
                }
                else if ((c.KeyChar == 'N') || (c.KeyChar == 'n'))
                {
                    break;
                }
            }
        }
    }
    catch (System.Transactions.TransactionException ex)
    {
        Console.WriteLine(ex);
    }
    catch
    {
        Console.WriteLine("Cannot complete transaction");
        throw;
    }
}

private static void WorkerThread(object transaction)
{
    //Create a DependentTransaction from the object passed to the WorkerThread
    DependentTransaction dTx = (DependentTransaction)transaction;

    //Sleep for 1 second to force the worker thread to delay
    Thread.Sleep(1000);

    //Pass the DependentTransaction to the scope, so that work done in the scope becomes part of the transaction passed to the worker thread
    using (TransactionScope ts = new TransactionScope(dTx))
    {
        //Perform transactional work here.

        //Call complete on the transaction scope
        ts.Complete();
    }

    //Call complete on the dependent transaction
    dTx.Complete();
}
Public Shared Sub Main()
    Try
        Using scope As TransactionScope = New TransactionScope()

            'Perform transactional work here.

            'Queue work item
            ThreadPool.QueueUserWorkItem(AddressOf WorkerThread, Transaction.Current.DependentClone(DependentCloneOption.BlockCommitUntilComplete))

            'Display transaction information
            Console.WriteLine("Transaction information:")
            Console.WriteLine("ID:             {0}", Transaction.Current.TransactionInformation.LocalIdentifier)
            Console.WriteLine("status:         {0}", Transaction.Current.TransactionInformation.Status)
            Console.WriteLine("isolationlevel: {0}", Transaction.Current.IsolationLevel)

            'Call Complete on the TransactionScope based on console input
            Dim c As ConsoleKeyInfo
            While (True)

                Console.Write("Complete the transaction scope? [Y|N] ")
                c = Console.ReadKey()
                Console.WriteLine()
                If (c.KeyChar = "Y") Or (c.KeyChar = "y") Then
                    scope.Complete()
                    Exit While
                ElseIf ((c.KeyChar = "N") Or (c.KeyChar = "n")) Then
                    Exit While
                End If
            End While
        End Using

    Catch ex As TransactionException
        Console.WriteLine(ex)
    Catch
        Console.WriteLine("Cannot complete transaction")
        Throw
    End Try
End Sub

Public Shared Sub WorkerThread(ByVal myTransaction As Object)

    'Create a DependentTransaction from the object passed to the WorkerThread
    Dim dTx As DependentTransaction
    dTx = CType(myTransaction, DependentTransaction)

    'Sleep for 1 second to force the worker thread to delay
    Thread.Sleep(1000)

    'Pass the DependentTransaction to the scope, so that work done in the scope becomes part of the transaction passed to the worker thread
    Using ts As TransactionScope = New TransactionScope(dTx)
        'Perform transactional work here.

        'Call complete on the transaction scope
        ts.Complete()
    End Using

    'Call complete on the dependent transaction
    dTx.Complete()
End Sub

Remarks

A dependent transaction can be obtained using the DependentClone method, with the DependentCloneOption parameter controlling what kind of dependent transaction to create. For more information on how this enumeration is used, see Managing Concurrency with DependentTransaction.

Applies to

See also