This documentation is archived and is not being maintained.

Enlistment Class

Facilitates communication between an enlisted transaction participant and the transaction manager during the final phase of the transaction.

Namespace: System.Transactions
Assembly: System.Transactions (in system.transactions.dll)

Public Class Enlistment
Dim instance As Enlistment

public class Enlistment
public class Enlistment
Not applicable.

When the EnlistVolatile and EnlistDurable methods of the Transaction object are invoked to enlist a participant in a transaction, they return this object describing the enlistment.

During the final phase of the transaction commit, the transaction manager passes this object to a resource manager implementing the IEnlistmentNotification interface that has enlisted in a transaction. Specifically, the transaction manager calls either the Commit or the Rollback method of the participant, depending on whether the latter has decided to commit or roll back the transaction. The participant should call the Done method of this object to let the transaction manager know that it has completed its work.

An enlistment can call the Done method at anytime before it has called Prepared in the prepare phase. By doing so, the enlistment is casting a read only vote, meaning that it votes commit on the transaction but does not need to receive the final outcome. Note that, after the Done method is called, the enlisted participant receives no further notifications from the transaction manager.

The following example shows an implementation of the IEnlistmentNotification interface, and when the Done method should be called.

Public Class EnlistmentClass
    Implements IEnlistmentNotification

    Public Sub Prepare(ByVal myPreparingEnlistment As PreparingEnlistment) Implements System.Transactions.IEnlistmentNotification.Prepare
        Console.WriteLine("Prepare notification received")

        'Perform transactional work

        'If work finished correctly, reply with prepared
    End Sub

    Public Sub Commit(ByVal myEnlistment As Enlistment) Implements System.Transactions.IEnlistmentNotification.Commit
        Console.WriteLine("Commit notification received")

        'Do any work necessary when commit notification is received

        'Declare done on the enlistment
    End Sub

    Public Sub Rollback(ByVal myEnlistment As Enlistment) Implements System.Transactions.IEnlistmentNotification.Rollback
        Console.WriteLine("Rollback notification received")

        'Do any work necessary when rollback notification is received

        'Declare done on the enlistment
    End Sub

    Public Sub InDoubt(ByVal myEnlistment As Enlistment) Implements System.Transactions.IEnlistmentNotification.InDoubt
        Console.WriteLine("In doubt notification received")

        'Do any work necessary when indout notification is received

        'Declare done on the enlistment
    End Sub
End Class

This type is thread safe.

Windows 98, Windows Server 2000 SP4, Windows Millennium Edition, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0