TransactionScope.Complete Método

Definição

Indica que todas as operações dentro do escopo foram concluídas com êxito.Indicates that all operations within the scope are completed successfully.

public:
 void Complete();
public void Complete ();
member this.Complete : unit -> unit
Public Sub Complete ()

Exceções

Este método já foi chamado uma vez.This method has already been called once.

Exemplos

O exemplo a seguir demonstra como usar a TransactionScope classe para definir um bloco de código para participar de uma transação.The following example demonstrates how to use the TransactionScope class to define a block of code to participate in a transaction.

// This function takes arguments for 2 connection strings and commands to create a transaction 
// involving two SQL Servers. It returns a value > 0 if the transaction is committed, 0 if the 
// transaction is rolled back. To test this code, you can connect to two different databases 
// on the same server by altering the connection string, or to another 3rd party RDBMS by 
// altering the code in the connection2 code block.
static public int CreateTransactionScope(
    string connectString1, string connectString2,
    string commandText1, string commandText2)
{
    // Initialize the return value to zero and create a StringWriter to display results.
    int returnValue = 0;
    System.IO.StringWriter writer = new System.IO.StringWriter();

    try
    {
        // Create the TransactionScope to execute the commands, guaranteeing
        // that both commands can commit or roll back as a single unit of work.
        using (TransactionScope scope = new TransactionScope())
        {
            using (SqlConnection connection1 = new SqlConnection(connectString1))
            {
                // Opening the connection automatically enlists it in the 
                // TransactionScope as a lightweight transaction.
                connection1.Open();

                // Create the SqlCommand object and execute the first command.
                SqlCommand command1 = new SqlCommand(commandText1, connection1);
                returnValue = command1.ExecuteNonQuery();
                writer.WriteLine("Rows to be affected by command1: {0}", returnValue);

                // If you get here, this means that command1 succeeded. By nesting
                // the using block for connection2 inside that of connection1, you
                // conserve server and network resources as connection2 is opened
                // only when there is a chance that the transaction can commit.   
                using (SqlConnection connection2 = new SqlConnection(connectString2))
                {
                    // The transaction is escalated to a full distributed
                    // transaction when connection2 is opened.
                    connection2.Open();

                    // Execute the second command in the second database.
                    returnValue = 0;
                    SqlCommand command2 = new SqlCommand(commandText2, connection2);
                    returnValue = command2.ExecuteNonQuery();
                    writer.WriteLine("Rows to be affected by command2: {0}", returnValue);
                }
            }

            // The Complete method commits the transaction. If an exception has been thrown,
            // Complete is not  called and the transaction is rolled back.
            scope.Complete();
        }
    }
    catch (TransactionAbortedException ex)
    {
        writer.WriteLine("TransactionAbortedException Message: {0}", ex.Message);
    }

    // Display messages.
    Console.WriteLine(writer.ToString());

    return returnValue;
}
'  This function takes arguments for 2 connection strings and commands to create a transaction 
'  involving two SQL Servers. It returns a value > 0 if the transaction is committed, 0 if the 
'  transaction is rolled back. To test this code, you can connect to two different databases 
'  on the same server by altering the connection string, or to another 3rd party RDBMS  
'  by altering the code in the connection2 code block.
Public Function CreateTransactionScope( _
  ByVal connectString1 As String, ByVal connectString2 As String, _
  ByVal commandText1 As String, ByVal commandText2 As String) As Integer

    ' Initialize the return value to zero and create a StringWriter to display results.
    Dim returnValue As Integer = 0
    Dim writer As System.IO.StringWriter = New System.IO.StringWriter

    Try
    ' Create the TransactionScope to execute the commands, guaranteeing
    '  that both commands can commit or roll back as a single unit of work.
        Using scope As New TransactionScope()
            Using connection1 As New SqlConnection(connectString1)
                ' Opening the connection automatically enlists it in the 
                ' TransactionScope as a lightweight transaction.
                connection1.Open()

                ' Create the SqlCommand object and execute the first command.
                Dim command1 As SqlCommand = New SqlCommand(commandText1, connection1)
                returnValue = command1.ExecuteNonQuery()
                writer.WriteLine("Rows to be affected by command1: {0}", returnValue)

                ' If you get here, this means that command1 succeeded. By nesting
                ' the using block for connection2 inside that of connection1, you
                ' conserve server and network resources as connection2 is opened
                ' only when there is a chance that the transaction can commit.   
                Using connection2 As New SqlConnection(connectString2)
                    ' The transaction is escalated to a full distributed
                    ' transaction when connection2 is opened.
                    connection2.Open()

                    ' Execute the second command in the second database.
                    returnValue = 0
                    Dim command2 As SqlCommand = New SqlCommand(commandText2, connection2)
                    returnValue = command2.ExecuteNonQuery()
                    writer.WriteLine("Rows to be affected by command2: {0}", returnValue)
                End Using
            End Using

        ' The Complete method commits the transaction. If an exception has been thrown,
        ' Complete is called and the transaction is rolled back.
        scope.Complete()
        End Using
    Catch ex As TransactionAbortedException
        writer.WriteLine("TransactionAbortedException Message: {0}", ex.Message)
    End Try

    ' Display messages.
    Console.WriteLine(writer.ToString())

    Return returnValue
End Function

Comentários

Quando estiver satisfeito com a conclusão bem-sucedida de todas as operações no escopo, você deve chamar esse método apenas uma vez para informar ao Gerenciador de transações que o estado em todos os recursos é consistente e que a transação pode ser confirmada.When you are satisfied that all operations within the scope are completed successfully, you should call this method only once to inform that transaction manager that the state across all resources is consistent, and the transaction can be committed. É uma prática recomendada colocar a chamada como a última instrução no using bloco.It is very good practice to put the call as the last statement in the using block.

Para obter mais informações sobre como esse método é usado, consulte o tópico implementando uma transação implícita usando escopo de transação .For more information on how this method is used, see the Implementing An Implicit Transaction Using Transaction Scope topic.

A falha ao chamar esse método anula a transação, pois o Gerenciador de transações interpreta isso como uma falha do sistema ou exceções geradas no escopo da transação.Failing to call this method aborts the transaction, because the transaction manager interprets this as a system failure, or exceptions thrown within the scope of transaction. No entanto, você também deve observar que chamar esse método não garante uma confirmação da transação.However, you should also note that calling this method does not guarantee a commit of the transaction. É simplesmente uma maneira de informar o Gerenciador de transações do seu status.It is merely a way of informing the transaction manager of your status. Depois de chamar esse método, você não poderá mais acessar a transação de ambiente por meio da Current propriedade e tentar fazer isso resultará na geração de uma exceção.After calling this method, you can no longer access the ambient transaction via the Current property, and trying to do so results in an exception being thrown.

O trabalho real de confirmação entre o Gerenciador de recursos ocorrerá na End Using instrução se o TransactionScope objeto tiver criado a transação.The actual work of commit between the resources manager happens at the End Using statement if the TransactionScope object created the transaction. Se ele não criou a transação, a confirmação ocorre sempre que Commit é chamado pelo proprietário do CommittableTransaction objeto.If it did not create the transaction, the commit occurs whenever Commit is called by the owner of the CommittableTransaction object. Nesse ponto, o Gerenciador de transações chama os gerenciadores de recursos e os informa para confirmação ou reversão, com base no fato de esse método ser chamado no TransactionScope objeto.At that point the Transaction Manager calls the resource managers and informs them to either commit or rollback, based on whether this method was called on the TransactionScope object.

Aplica-se a