Поделиться через


Метод DTSBufferManagerClass.FindColumnByLineageID

Gets the location of a column in the specified IDTSBuffer100 object.

Пространство имен:  Microsoft.SqlServer.Dts.Pipeline.Wrapper
Сборка:  Microsoft.SqlServer.DTSPipelineWrap (в Microsoft.SqlServer.DTSPipelineWrap.dll)

Синтаксис

'Декларация
Public Overridable Function FindColumnByLineageID ( _
    hBufferType As Integer, _
    nLineageID As Integer _
) As Integer
'Применение
Dim instance As DTSBufferManagerClass 
Dim hBufferType As Integer 
Dim nLineageID As Integer 
Dim returnValue As Integer 

returnValue = instance.FindColumnByLineageID(hBufferType, _
    nLineageID)
public virtual int FindColumnByLineageID(
    int hBufferType,
    int nLineageID
)
public:
virtual int FindColumnByLineageID(
    [InAttribute] int hBufferType, 
    [InAttribute] int nLineageID
)
abstract FindColumnByLineageID : 
        hBufferType:int * 
        nLineageID:int -> int  
override FindColumnByLineageID : 
        hBufferType:int * 
        nLineageID:int -> int
public function FindColumnByLineageID(
    hBufferType : int, 
    nLineageID : int
) : int

Параметры

Возвращаемое значение

Тип: System.Int32
An Integer that indicates the location, by index, of the column in the IDTSBuffer100.

Реализует

IDTSBufferManager100.FindColumnByLineageID(Int32, Int32)

Замечания

This method locates the column of an IDTSInput100 or IDTSOutput100 in the specified IDTSBuffer100. This method is necessary because an instance of a buffer contains all of the IDTSOutputColumn100 objects defined in the IDTSOutputColumnCollection100 of the components in a graph. Components cannot rely on using the index location of an output column or input column as the index of that column in a buffer row. Because of this, components must use the FindColumnByLineageID method to locate the columns in the buffer.

Примеры

The following code example shows how a transformation component that does not have output columns uses FindColumnByLineageID to locate its input columns in the buffer.

int[] bufferColumnIndex;
public override void PreExecute()
{
    IDTSInput100 input = ComponentMetaData.InputCollection[0];
    bufferColumnIndex = new int[BufferManager.GetColumnCount(input.Buffer)];

    for( int col=0; col < input.InputColumnCollection.Count; col++)
    {
        IDTSInputColumn100 iCol = input.InputColumnCollection[col];
        bufferColumnIndex[col] = BufferManager.FindColumnByLineageID(input.Buffer, iCol.LineageID);
    }
}
Private bufferColumnIndex As Integer() 

Public Overloads Overrides Sub PreExecute() 
 Dim input As IDTSInput100 = ComponentMetaData.InputCollection(0) 
 bufferColumnIndex = New Integer(BufferManager.GetColumnCount(input.Buffer) - 1) {} 
 Dim col As Integer = 0 
 While col < input.InputColumnCollection.Count 
   Dim iCol As IDTSInputColumn100 = input.InputColumnCollection(col) 
   bufferColumnIndex(col) = BufferManager.FindColumnByLineageID(input.Buffer, iCol.LineageID) 
   col -= 1 
 End While 
End Sub

См. также

Справочник

DTSBufferManagerClass Класс

Пространство имен Microsoft.SqlServer.Dts.Pipeline.Wrapper