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SqlCeDataReader.GetBytes Method

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

Namespace: System.Data.SqlServerCe
Assembly: System.Data.SqlServerCe (in system.data.sqlserverce.dll)

Syntax

'Declaration
Public Overrides Function GetBytes ( _
    ordinal As Integer, _
    dataIndex As Long, _
    buffer As Byte(), _
    bufferIndex As Integer, _
    length As Integer _
) As Long
'Usage
Dim instance As SqlCeDataReader
Dim ordinal As Integer
Dim dataIndex As Long
Dim buffer As Byte()
Dim bufferIndex As Integer
Dim length As Integer
Dim returnValue As Long

returnValue = instance.GetBytes(ordinal, dataIndex, buffer, bufferIndex, length)

public override long GetBytes (
    int ordinal,
    long dataIndex,
    byte[] buffer,
    int bufferIndex,
    int length
)

public:
virtual long long GetBytes (
    int ordinal, 
    long long dataIndex, 
    array<unsigned char>^ buffer, 
    int bufferIndex, 
    int length
) override

public long GetBytes (
    int ordinal, 
    long dataIndex, 
    byte[] buffer, 
    int bufferIndex, 
    int length
)

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

Not applicable.

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.

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 a null reference (Nothing in Visual Basic), GetBytes returns the length of the field in bytes.

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

Platforms

Windows CE, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows XP Professional x64 Edition, Windows XP SP2

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

Version Information

.NET Framework

Supported in: 3.0

.NET Compact Framework

Supported in: 2.0, 1.0

See Also

Reference

SqlCeDataReader Class
SqlCeDataReader Members
System.Data.SqlServerCe Namespace