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SqlDataReader.GetBytes Method

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

Namespace: System.Data.SqlClient
Assembly: System.Data (in

public override long GetBytes (
	int i,
	long dataIndex,
	byte[] buffer,
	int bufferIndex,
	int length
public long GetBytes (
	int i, 
	long dataIndex, 
	byte[] buffer, 
	int bufferIndex, 
	int length
public override function GetBytes (
	i : int, 
	dataIndex : long, 
	buffer : byte[], 
	bufferIndex : int, 
	length : int
) : long



The zero-based column ordinal.


The index within the field from which to begin the read operation.


The buffer into which to read the stream of bytes.


The index for buffer to begin the write operation.


The maximum length to copy into the buffer.

Return Value

The actual number of bytes read.

GetBytes returns the number of available bytes in the field. Most of the time 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, if the SqlDataReader 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 a null reference (Nothing in Visual Basic), GetBytes returns the length of the entire field in bytes, not the remaining size based on the buffer offset parameter.

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

Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.

.NET Framework

Supported in: 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 2.0, 1.0