IDTSBuffer90.GetBLOBData Method

Статья
12/15/2008

Retrieves an array of bytes from a binary large object (BLOB) stored in a column of a IDTSBuffer90.

Пространство имен: Microsoft.SqlServer.Dts.Pipeline.Wrapper
Сборка: Microsoft.SqlServer.DTSPipelineWrap (in microsoft.sqlserver.dtspipelinewrap.dll)

Синтаксис

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

void GetBLOBData (
    [InAttribute] int hRow,
    [InAttribute] int hCol,
    [InAttribute] uint dwOffset,
    [InAttribute] ref byte lpPointer,
    [InAttribute] 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
)

void GetBLOBData (
    /** @attribute InAttribute() */ int hRow, 
    /** @attribute InAttribute() */ int hCol, 
    /** @attribute InAttribute() */ UInt32 dwOffset, 
    /** @attribute InAttribute() */ /** @ref */ byte lpPointer, 
    /** @attribute InAttribute() */ UInt32 dwLength, 
    /** @attribute OutAttribute() */ /** @ref */ UInt32 lpdwWritten
)

JScript не поддерживает передачу аргументов типа, содержащего значение, по ссылке.

Параметры

hRow
The row handle.

hCol
The column handle.

dwOffset
The location in the byte data stored in the column from which to begin reading bytes.

lpPointer
A reference parameter that points to the first byte in the array of bytes that are retrieved.

dwLength
The number of bytes to retrieve from the column.

lpdwWritten
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 IDTSBuffer90. This method is typically used to recursively when sequentially reading BLOB sections.

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

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

См. также

Справочник

IDTSBuffer90 Interface
IDTSBuffer90 Members
Microsoft.SqlServer.Dts.Pipeline.Wrapper Namespace

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