IDbTransaction.Rollback Methode

Definition

Führt einen Rollback für eine Transaktion aus einem ausstehenden Zustand durch.Rolls back a transaction from a pending state.

public:
 void Rollback();
public void Rollback ();
abstract member Rollback : unit -> unit
Public Sub Rollback ()

Ausnahmen

Fehler beim Ausführen eines Commits der Transaktion.An error occurred while trying to commit the transaction.

Es wurde bereits ein Commit bzw. ein Rollback für die Transaktion ausgeführt.The transaction has already been committed or rolled back.

- oder --or-

Die Verbindung ist unterbrochen.The connection is broken.

Beispiele

Im folgenden Beispiel werden SqlConnection Instanzen der abgeleiteten Klassen und eine SqlTransactionerstellt.The following example creates instances of the derived classes, SqlConnection and a SqlTransaction. Außerdem wird veranschaulicht, wie die BeginTransactionMethoden, und Rollback verwendet werden Commit.It also demonstrates how to use the BeginTransaction, Commit, and Rollback methods.

private static void ExecuteSqlTransaction(string connectionString)
{
    using (SqlConnection connection = new SqlConnection(connectionString))
    {
        connection.Open();

        SqlCommand command = connection.CreateCommand();
        SqlTransaction transaction;

        // Start a local transaction.
        transaction = connection.BeginTransaction("SampleTransaction");

        // Must assign both transaction object and connection
        // to Command object for a pending local transaction
        command.Connection = connection;
        command.Transaction = transaction;

        try
        {
            command.CommandText =
                "Insert into Region (RegionID, RegionDescription) VALUES (100, 'Description')";
            command.ExecuteNonQuery();
            command.CommandText =
                "Insert into Region (RegionID, RegionDescription) VALUES (101, 'Description')";
            command.ExecuteNonQuery();

            // Attempt to commit the transaction.
            transaction.Commit();
            Console.WriteLine("Both records are written to database.");
        }
        catch (Exception ex)
        {
            Console.WriteLine("Commit Exception Type: {0}", ex.GetType());
            Console.WriteLine("  Message: {0}", ex.Message);

            // Attempt to roll back the transaction.
            try
            {
                transaction.Rollback();
            }
            catch (Exception ex2)
            {
                // This catch block will handle any errors that may have occurred
                // on the server that would cause the rollback to fail, such as
                // a closed connection.
                Console.WriteLine("Rollback Exception Type: {0}", ex2.GetType());
                Console.WriteLine("  Message: {0}", ex2.Message);
            }
        }
    }
}
Private Sub ExecuteSqlTransaction(ByVal connectionString As String)
    Using connection As New SqlConnection(connectionString)
        connection.Open()

        Dim command As SqlCommand = connection.CreateCommand()
        Dim transaction As SqlTransaction

        ' Start a local transaction
        transaction = connection.BeginTransaction("SampleTransaction")

        ' Must assign both transaction object and connection
        ' to Command object for a pending local transaction.
        command.Connection = connection
        command.Transaction = transaction

        Try
            command.CommandText = _
              "Insert into Region (RegionID, RegionDescription) VALUES (100, 'Description')"
            command.ExecuteNonQuery()
            command.CommandText = _
              "Insert into Region (RegionID, RegionDescription) VALUES (101, 'Description')"

            command.ExecuteNonQuery()

            ' Attempt to commit the transaction.
            transaction.Commit()
            Console.WriteLine("Both records are written to database.")

        Catch ex As Exception
            Console.WriteLine("Commit Exception Type: {0}", ex.GetType())
            Console.WriteLine("  Message: {0}", ex.Message)

            ' Attempt to roll back the transaction.
            Try
                transaction.Rollback()

            Catch ex2 As Exception
                ' This catch block will handle any errors that may have occurred
                ' on the server that would cause the rollback to fail, such as
                ' a closed connection.
                Console.WriteLine("Rollback Exception Type: {0}", ex2.GetType())
                Console.WriteLine("  Message: {0}", ex2.Message)
            End Try
        End Try
    End Using
End Sub

Hinweise

Für die Transaktion kann nur ein Rollback von einem ausstehenden Zustand ausgeführt BeginTransaction werden (nachdem aufgerufen wurde, Commit aber bevor aufgerufen wird).The transaction can only be rolled back from a pending state (after BeginTransaction has been called, but before Commit is called).

Hinweise für Ausführende

Stellen Sie beim Überschreiben Rollback ineinerabgeleitetenKlassesicher,dassSiedie-MethodederBasisklasseaufzurufen.Rollback()When overriding Rollback() in a derived class, be sure to call the base class's Rollback method.

Gilt für:

Siehe auch