SqlTransaction.Rollback Metoda

public:
 override void Rollback();

public:
 virtual void Rollback();

public override void Rollback ();

public void Rollback ();

override this.Rollback : unit -> unit

abstract member Rollback : unit -> unit
override this.Rollback : unit -> unit

Public Overrides Sub Rollback ()

Public Sub Rollback ()

Implementuje

Výjimky

Příklady

Následující příklad vytvoří SqlConnection a SqlTransaction. Ukazuje také, jak používat BeginTransactionmetody , Commita Rollback . Transakce se vrátí zpět při jakékoli chybě. Try / Catch zpracování chyb se používá ke zpracování chyb při pokusu o potvrzení nebo vrácení transakce zpět.

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();

        // 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()

        ' 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

Poznámky

Metoda Rollback je ekvivalentem příkazu Transact-SQL ROLLBACK TRANSACTION. Další informace najdete v tématu ROLLBACK TRANSACTION (Transact-SQL) .

Transakce může být vrácena zpět pouze z čekajícího stavu (po BeginTransaction byla volána, ale před Commit je volána). Transakce se vrátí zpět v případě, že je odstraněna před Commit nebo Rollback je volána.

Další informace o transakcích SQL Server najdete v tématu Transakce (Transact-SQL).

Viz také

• Místní transakce
• Přehled ADO.NET

public:
 void Rollback(System::String ^ transactionName);

public void Rollback (string transactionName);

override this.Rollback : string -> unit

member this.Rollback : string -> unit

Public Sub Rollback (transactionName As String)

Parametry

Výjimky

Příklady

Následující příklad vytvoří SqlConnection a SqlTransaction. Ukazuje také, jak používat BeginTransactionmetody , Commita Rollback . Transakce se vrátí zpět při jakékoli chybě. Try / Catch zpracování chyb se používá ke zpracování chyb při pokusu o potvrzení nebo vrácení transakce zpět.

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("SampleTransaction");
            }
            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("Exception Type: {0}", ex.GetType())
            Console.WriteLine("  Message: {0}", ex.Message)

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

            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

Poznámky

Metoda Rollback je ekvivalentem příkazu Transact-SQL ROLLBACK TRANSACTION. Další informace najdete v tématu Transakce (Transact-SQL).

Transakce může být vrácena zpět pouze z čekajícího stavu (po BeginTransaction byla volána, ale před Commit je volána). Transakce se vrátí zpět, pokud je odstraněna před Commit nebo Rollback je volána.

Další informace o transakcích SQL Server najdete v tématu Transakce (Transact-SQL).

Viz také

• Provádění transakce
• Přehled ADO.NET