SqlCeConnection.BeginTransaction Method ()

Inicia uma transação do banco de dados.

Namespace: System.Data.SqlServerCe
Assembly: System.Data.SqlServerCe (em system.data.sqlserverce.dll)

Sintaxe

'Declaração
Public Function BeginTransaction As SqlCeTransaction

public SqlCeTransaction BeginTransaction ()

public:
SqlCeTransaction^ BeginTransaction ()

public SqlCeTransaction BeginTransaction ()

public function BeginTransaction () : SqlCeTransaction

Valor de retorno

Um objeto que representa a nova transação.

Comentários

Confirme ou reverta a conexão explicitamente, usando o método Commit ou Rollback.

Exemplo

O exemplo a seguir cria uma SqlCeConnection e uma SqlCeTransaction e, em seguida, demonstra como usar os métodos BeginTransaction, Commit e Rollback.

Dim conn As New SqlCeConnection("Data Source = MyDatabase.sdf; Password ='<pwd>'")
conn.Open()

' Start a local transaction
'
Dim tx As SqlCeTransaction = conn.BeginTransaction()

' By default, commands run in auto-commit mode; 
'
Dim cmd1 As SqlCeCommand = conn.CreateCommand()

' You may create multiple commands on the same connection
'
Dim cmd2 As SqlCeCommand = conn.CreateCommand()

' To enlist a command in a transaction, set the Transaction property
'
cmd1.Transaction = tx

Try
    cmd1.CommandText = "INSERT INTO Shippers ([Company Name]) VALUES ('Northwind Traders')"
    cmd1.ExecuteNonQuery()

    ' Auto-commited because cmd2 is not enlisted in a transaction
    '
    cmd2.CommandText = "INSERT INTO Employees ([Last Name], [First Name]) VALUES ('Decker', 'Barbara')"
    cmd2.ExecuteNonQuery()

    ' This will cause referential constraint violation
    '
    cmd1.CommandText = "DELETE FROM Products WHERE [Product ID] = 1"
    cmd1.ExecuteNonQuery()

    ' Commit the changes to disk if everything above succeeded
    '
    tx.Commit()
Catch
    tx.Rollback()
Finally
    conn.Close()
End Try

SqlCeConnection conn = new SqlCeConnection("Data Source = MyDatabase.sdf; Password ='<pwd>'");
conn.Open();

// Start a local transaction
//
SqlCeTransaction tx = conn.BeginTransaction();

// By default, commands run in auto-commit mode; 
//
SqlCeCommand cmd1 = conn.CreateCommand();

// You may create multiple commands on the same connection
//
SqlCeCommand cmd2 = conn.CreateCommand();

// To enlist a command in a transaction, set the Transaction property
//
cmd1.Transaction = tx;

try
{
    cmd1.CommandText = "INSERT INTO Shippers ([Company Name]) VALUES ('Northwind Traders')";
    cmd1.ExecuteNonQuery();

    // Auto-commited because cmd2 is not enlisted in a transaction
    //
    cmd2.CommandText = "INSERT INTO Employees ([Last Name], [First Name]) VALUES ('Decker', 'Barbara')";
    cmd2.ExecuteNonQuery();

    // This will cause referential constraint violation
    //
    cmd1.CommandText = "DELETE FROM Products WHERE [Product ID] = 1";
    cmd1.ExecuteNonQuery();

    // Commit the changes to disk if everything above succeeded
    //
    tx.Commit();
}
catch (Exception)
{
    tx.Rollback();
}
finally
{
    conn.Close();
}

Segurança de thread

Quaisquer membros estáticos públicos (compartilhados no Microsoft Visual Basic) desse tipo são thread safe. Não há garantia de que qualquer membro de instância seja thread safe.

Plataformas

Plataformas de desenvolvimento

Windows Vista, Windows Mobile 5.0, Windows XP Professional with Service Pack 2 (SP2), Windows Server 2003, Windows Mobile 2003 for Pocket PC, Windows CE 5.0
Informações de versão
.NET Framework e NET Compact Framework
Com suporte no 3.5
.NET Framework
Com suporte no 3.0
.NET Compact Framework e .Net Framework
Com suporte no 2.0

Consulte também

Referência

SqlCeConnection Class
SqlCeConnection Members
System.Data.SqlServerCe Namespace