PipelineComponent.AcquireConnections Method

Статья
12/15/2008

Establishes a connection to a connection manager.

Пространство имен: Microsoft.SqlServer.Dts.Pipeline
Сборка: Microsoft.SqlServer.PipelineHost (in microsoft.sqlserver.pipelinehost.dll)

Синтаксис

'Декларация
Public Overridable Sub AcquireConnections ( _
    transaction As Object _
)

public virtual void AcquireConnections (
    Object transaction
)

public:
virtual void AcquireConnections (
    Object^ transaction
)

public void AcquireConnections (
    Object transaction
)

public function AcquireConnections (
    transaction : Object
)

Параметры

transaction
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.

Пример

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 IDTSConnectionManager90 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 IDTSConnectionManager90 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

Синхронизация потоков

Any public static (Shared in Microsoft Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Платформы

Платформы разработки

Список поддерживаемых платформ см. в разделе Hardware and Software Requirements for Installing SQL Server 2005.

Целевые платформы