Xceed .NET Libraries Documentation
Xceed.Compression.Formats Assembly / Xceed.Compression.Formats Namespace / XceedCompressedStreamEx Class / Compress Method / Compress(Byte[],CompressionMethod,CompressionLevel) Method
The array of bytes to compress.
A Xceed.Compression.CompressionMethod value representing the compression method to use.
A Xceed.Compression.CompressionLevel value representing the compression level to use.


In This Topic
    Compress(Byte[],CompressionMethod,CompressionLevel) Method
    In This Topic
    Compresses an array of bytes using the extended Xceed compression format with the specified compression method and level. Use this method to compress data compatible with the ActiveX Xceed Zip Compression Library (XceedCompression object).
    Syntax
    'Declaration
     
    Public Overloads Shared Shadows Function Compress( _
       ByVal buffer() As Byte, _
       ByVal method As CompressionMethod, _
       ByVal level As CompressionLevel _
    ) As Byte()
    'Usage
     
    Dim buffer() As Byte
    Dim method As CompressionMethod
    Dim level As CompressionLevel
    Dim value() As Byte
     
    value = XceedCompressedStreamEx.Compress(buffer, method, level)
    public new static byte[] Compress( 
       byte[] buffer,
       CompressionMethod method,
       CompressionLevel level
    )

    Parameters

    buffer
    The array of bytes to compress.
    method
    A Xceed.Compression.CompressionMethod value representing the compression method to use.
    level
    A Xceed.Compression.CompressionLevel value representing the compression level to use.

    Return Value

    An array of bytes containing the compressed data.
    Remarks

    If the data to compress is not a byte array, it will need to be converted into a byte array before it can be compressed. This can be done, in the case of a string, using the System.Text.Encoding.GetBytes(System.Char[]) method of the System.Text.Encoding class.

    The Stored compression method is not supported. The compression level only applies to the Deflated and Deflated64 compression methods.  It does not apply to the BZip2, BWT, or PPMd compression methods.

    The PPMd algorithm uses a custom memory management system called SubAllocator. In a zip file, the memory size the SubAllocator uses is defined in the WinZip PPMd header for the compressed file and this header's value is used when decompressing the data. In general, WinZip uses 64Mb. Since the algorithm used was not optimized from the original PPMd version I revision 1, the SubAllocator initially requires the total amount of memory specified in the PPMd compressor. This means you must have at least 64 free Mb of RAM when using this compression method.

    Requirements

    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

    See Also