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Метод GetBLOBData

Retrieves an array of bytes from a binary large object (BLOB) stored in a column of a IDTSBuffer100.

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

Синтаксис

'Декларация
Sub GetBLOBData ( _
    hRow As Integer, _
    hCol As Integer, _
    dwOffset As UInteger, _
    ByRef lpPointer As Byte, _
    dwLength As UInteger, _
    <OutAttribute> ByRef lpdwWritten As UInteger _
)
'Применение
Dim instance As IDTSBuffer100
Dim hRow As Integer
Dim hCol As Integer
Dim dwOffset As UInteger
Dim lpPointer As Byte
Dim dwLength As UInteger
Dim lpdwWritten As UInteger

instance.GetBLOBData(hRow, hCol, dwOffset, _
    lpPointer, dwLength, lpdwWritten)

void GetBLOBData(
    int hRow,
    int hCol,
    uint dwOffset,
    ref byte lpPointer,
    uint dwLength,
    out uint lpdwWritten
)

void GetBLOBData(
    [InAttribute] int hRow, 
    [InAttribute] int hCol, 
    [InAttribute] unsigned int dwOffset, 
    [InAttribute] unsigned char% lpPointer, 
    [InAttribute] unsigned int dwLength, 
    [OutAttribute] unsigned int% lpdwWritten
)

abstract GetBLOBData : 
        hRow:int * 
        hCol:int * 
        dwOffset:uint32 * 
        lpPointer:byte byref * 
        dwLength:uint32 * 
        lpdwWritten:uint32 byref -> unit 

function GetBLOBData(
    hRow : int, 
    hCol : int, 
    dwOffset : uint, 
    lpPointer : byte, 
    dwLength : uint, 
    lpdwWritten : uint
)

Параметры

  • dwOffset
    Тип: System. . :: . .UInt32
    The location in the byte data stored in the column from which to begin reading bytes.
  • lpPointer
    Тип: System. . :: . .Byte%
    A reference parameter that points to the first byte in the array of bytes that are retrieved.
  • lpdwWritten
    Тип: System. . :: . .UInt32%
    An out parameter that indicates the number of bytes written to the lpPointer parameter.

Замечания

When retrieving data from a column that contains a BLOB, such as a DT_IMAGE, specify the starting location in the BLOB with the dwOffset parameter, and the number of bytes to retrieve in the dwLength parameter. Retrieving the data from a BLOB column in sections is recommended to avoid situations that may occur if the size of the data in the BLOB is larger than the available memory on the computer.

This method is used to retrieve a section of bytes from the column specified by the hCol parameter in the IDTSBuffer100. This method is typically used to recursively when sequentially reading BLOB sections.