IDbTransaction Interface

Definição

public interface class IDbTransaction : IDisposable

public interface IDbTransaction : IDisposable

type IDbTransaction = interface
    interface IDisposable

Public Interface IDbTransaction
Implements IDisposable

Derivado

System.Data.Common.DbTransaction

System.Data.Odbc.OdbcTransaction

System.Data.OleDb.OleDbTransaction

System.Data.OracleClient.OracleTransaction

System.Data.SqlClient.SqlTransaction

Implementações

IDisposable

Exemplos

O exemplo seguinte cria instâncias das classes derivadas, SqlConnection e SqlTransaction. Também demonstra como usar os BeginTransactionmétodos , Commit, e Rollback .

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

Observações

A IDbTransaction interface permite que uma classe herdadora implemente uma classe Transaction, que representa a transação a ser realizada numa fonte de dados. Para mais informações sobre classes de Transações, consulte Transações e Concorrência.

Uma aplicação não cria diretamente uma instância da IDbTransaction interface, mas cria uma instância de uma classe que herda IDbTransaction.

As classes que herdam IDbTransaction devem implementar os membros herdados, e normalmente definem membros adicionais para adicionar funcionalidades específicas do fornecedor. Por exemplo, a IDbTransaction interface define o Commit método. Por sua vez, a OleDbTransaction classe herda esta propriedade e também define o Begin método.

Notas para Implementadores

Para promover a consistência entre .NET fornecedores de dados do Framework, nomeie a classe herdadora na forma Prv Transaction, onde Prv é o prefixo uniforme dado a todas as classes num determinado espaço de nomes do fornecedor de dados .NET Framework. Por exemplo, Sql é o prefixo da SqlTransaction classe no System.Data.SqlClient namespace.