Метод AcquireConnections
Establishes a connection to a connection manager.
Пространство имен: Microsoft.SqlServer.Dts.Pipeline
Сборка: Microsoft.SqlServer.PipelineHost (в Microsoft.SqlServer.PipelineHost.dll)
Синтаксис
'Декларация
Public Overridable Sub AcquireConnections ( _
transaction As Object _
)
'Применение
Dim instance As PipelineComponent
Dim transaction As Object
instance.AcquireConnections(transaction)
public virtual void AcquireConnections(
Object transaction
)
public:
virtual void AcquireConnections(
Object^ transaction
)
abstract AcquireConnections :
transaction:Object -> unit
override AcquireConnections :
transaction:Object -> unit
public function AcquireConnections(
transaction : Object
)
Параметры
- transaction
Тип System. . :: . .Object
The transaction the connection is participating in.
Замечания
AcquireConnections is called during both component design and execution. Components that connect to external data sources should establish their connections during this method. Any connection established during this method should be cached in a local member variable and released in the ReleaseConnections method. Connections should only be established during AcquireConnections.
Примеры
The following example shows a component that connects to an ADO.NET connection manager during AcquireConnections.
public override void AcquireConnections(object transaction)
{
if (ComponentMetaData.RuntimeConnectionCollection[0].ConnectionManager != null)
{
// Convert the native IDTSConnectionManager100 to the managed ConnectionManager,
// then retrieve the underlying connection through the InnerObject.
ConnectionManager cm = Microsoft.SqlServer.Dts.Runtime.DtsConvert.ToConnectionManager(ComponentMetaData.RuntimeConnectionCollection[0].ConnectionManager);
ConnectionManagerAdoNet cmado = cm.InnerObject as ConnectionManagerAdoNet;
// If the InnerObject is not an ConnectionManagerAdoNet, then
// the cmado object is null.
if( cmado == null )
throw new Exception("The ConnectionManager " + cm.Name + " is not an ADO.NET connection.");
// Get the underlying connection object.
this.oledbConnection = cmado.AcquireConnection(transaction) as OleDbConnection;
if( this.oledbConnection == null )
throw new Exception("The ConnectionManager " + cm.Name + " is not an ADO.NET connection.");
isConnected = true;
}
}
Public Overrides Sub AcquireConnections(ByVal transaction As Object)
If Not (ComponentMetaData.RuntimeConnectionCollection(0).ConnectionManager Is Nothing) Then
' Convert the native IDTSConnectionManager100 to the managed ConnectionManager,
' then retrieve the underlying connection through the InnerObject.
Dim cm As ConnectionManager = Microsoft.SqlServer.Dts.Runtime.DtsConvert.ToConnectionManager(ComponentMetaData.RuntimeConnectionCollection(0).ConnectionManager)
Dim cmado As ConnectionManagerAdoNet = CType(ConversionHelpers.AsWorkaround(cm.InnerObject, GetType(ConnectionManagerAdoNet)), ConnectionManagerAdoNet)
' If the InnerObject is not an ConnectionManagerAdoNet, then
' the cmado object is null.
If cmado Is Nothing Then
Throw New Exception("The ConnectionManager " + cm.Name + " is not an ADO.NET connection.")
End If
' Get the underlying connection object.
Me.oledbConnection = CType(ConversionHelpers.AsWorkaround(cmado.AcquireConnection(transaction), GetType(OleDbConnection)), OleDbConnection)
If Me.oledbConnection Is Nothing Then
Throw New Exception("The ConnectionManager " + cm.Name + " is not an ADO.NET connection.")
End If
isConnected = True
End If
End Sub