Méthode SqlCeConnection.CreateCommand
Crée et retourne un objet SqlCeCommand associé à SqlCeConnection.
Espace de noms : System.Data.SqlServerCe
Assembly : System.Data.SqlServerCe (en System.Data.SqlServerCe.dll)
Syntaxe
'Déclaration
Public Function CreateCommand As SqlCeCommand
'Utilisation
Dim instance As SqlCeConnection
Dim returnValue As SqlCeCommand
returnValue = instance.CreateCommand()
public SqlCeCommand CreateCommand()
public:
SqlCeCommand^ CreateCommand()
member CreateCommand : unit -> SqlCeCommand
public function CreateCommand() : SqlCeCommand
Valeur de retour
Type : System.Data.SqlServerCe.SqlCeCommand
un objet SqlCeCommand.
Exemples
L'exemple suivant illustre l'utilisation de la méthode CreateCommand pour créer un objet SqlCeCommand.
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();
}