SqlCeDataReader.GetBytes Method

项目
10/16/2007

Note: This namespace, class, or member is supported only in version 1.1 of the .NET Framework.

Reads a stream of bytes from the specified column offset into the buffer as an array starting at the given buffer offset.

  [Visual Basic]
  Public Overridable Function GetBytes( _
   ByVal 
  ordinal
   As Integer, _
   ByVal dataIndex As Long, _
   ByVal buffer() As Byte, _
   ByVal bufferIndex As Integer, _
   ByVal length As Integer _
) As Long Implements IDataRecord.GetBytes
[C#]
public virtual long GetBytes(int ordinal,long dataIndex,byte[] buffer,int bufferIndex,int length
);
[C++]
public: virtual __int64 GetBytes(int ordinal,__int64 dataIndex,unsigned char buffer __gc[],int bufferIndex,int length
);
[JScript]
public function GetBytes(
   ordinal : int,
 dataIndex : long,
 buffer : Byte[],
 bufferIndex : int,
 length : int) : long;

Parameters

ordinal
The zero-based column ordinal.
dataIndex
The index within the field from which to begin the read operation.
buffer
The buffer into which to read the stream of bytes.
bufferIndex
The index for buffer to begin the read operation.
length
The maximum length to copy into the buffer.

Return Value

The actual number of bytes read.

Implements

IDataRecord.GetBytes

Exceptions

Exception Type	Condition
InvalidOperationException	The operation is not valid. The SqlCeDataReader may be positioned after the last row in the result set.

Remarks

GetBytes returns the number of available bytes in the field. In most cases, this is the exact length of the field. However, the number returned may be less than the true length of the field if GetBytes has already been used to obtain bytes from the field. This may be the case, for example, when the SqlCeDataReader is reading a large data structure into a buffer. For more information, see the SequentialAccess setting for CommandBehavior.

If you pass a buffer that is null, GetBytes returns the length of the field in bytes.

No conversions are performed; therefore, the data retrieved must already be a byte array.

Requirements

Platforms: .NET Compact Framework

.NET Framework Security:

Full trust for the immediate caller. This member cannot be used by partially trusted code. For more information, see Using Libraries From Partially Trusted Code

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