'Declaration
 
Public MustOverride Function Compress( _

   ByVal buffer() As Byte, _

   ByVal offset As Integer, _

   ByVal count As Integer, _

   ByVal endOfData As Boolean, _

   ByRef compressed() As Byte _

) As Integer

'Usage
 
Dim instance As Compressor

Dim buffer() As Byte

Dim offset As Integer

Dim count As Integer

Dim endOfData As Boolean

Dim compressed() As Byte

Dim value As Integer

 

value = instance.Compress(buffer, offset, count, endOfData, compressed)

public abstract int Compress( 

   byte[] buffer,

   int offset,

   int count,

   bool endOfData,

   out byte[] compressed

)

Parameters

buffer

An array of bytes to compress. A maximum of count bytes are taken from this array and compressed.

offset

The byte offset in buffer at which to begin taking the data to compress.

count

The maximum number of bytes to be taken from buffer.

endOfData

Indicates if this call ends the stream of data to compress.

compressed

An array of bytes containing the compressed data. Can be empty.

Return Value

During a compression session, the compression engine can choose to keep the data to compress in an internal buffer and return an empty array after a call to Compress. Many compression algorithms do this to get optimum compression by examining a certain number of bytes before compressing anything.

A call to Compress with an empty buffer or a count of zero tells the compression engine to flush its internal buffer and return the compressed data. This may degrade the compression ratio.

When Compress is called with the parameter endOfData set to True, the compression session is closed and all of the remaining compressed data is returned. The next call to Compress will create a new compression session.

The compressed array may have a Length greater than the number of bytes returned by the call to Compress.

Target Platforms: Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

Reference

Compressor Class
Compressor Members