SqlCeCommand.Transaction Propiedad
Obtiene o establece la transacción en la que se ejecuta SqlCeCommand.
Espacio de nombres: System.Data.SqlServerCe
Ensamblado: System.Data.SqlServerCe (en System.Data.SqlServerCe.dll)
Sintaxis
'Declaración
Public Property Transaction As SqlCeTransaction
Get
Set
'Uso
Dim instance As SqlCeCommand
Dim value As SqlCeTransaction
value = instance.Transaction
instance.Transaction = value
public SqlCeTransaction Transaction { get; set; }
public:
property SqlCeTransaction^ Transaction {
SqlCeTransaction^ get ();
void set (SqlCeTransaction^ value);
}
member Transaction : SqlCeTransaction with get, set
function get Transaction () : SqlCeTransaction
function set Transaction (value : SqlCeTransaction)
Valor de la propiedad
Tipo: System.Data.SqlServerCe.SqlCeTransaction
Objeto SqlCeTransaction. El valor predeterminado es nulles una referencia NULL (Nothing en Visual Basic)..
Comentarios
No puede establecerse el valor de la propiedad Transaction, si ya se ha especificado un valor y se está ejecutando el comando. Si se establece la propiedad de transacción de un objeto SqlCeTransaction que no está conectado al mismo SqlCeConnection que el objeto SqlCeCommand, la próxima vez que se intente ejecutar una instrucción se producirá una excepción.
Si se ejecuta SqlCeCommand con SqlCeTransaction establecida en nulles una referencia NULL (Nothing en Visual Basic)., el comando se ejecuta en modo de confirmación automática, por lo que cada instrucción se ejecuta en su propia transacción.
Ejemplos
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();
}