(VB.NET) Replacment for Deprecated Crypt2 Compress Functions

The Chilkat Crypt2 compression functions are deprecated and will be removed. This example shows how to duplicate the functionality using the Chilkat Compression class.

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Dim crypt As New Chilkat.Crypt2

' Create data to be compressed.
Dim sb As New Chilkat.StringBuilder
Dim i As Integer = 0
While i < 25
    sb.Append("Hello World, this is a test." & vbCrLf)
    i = i + 1
End While

' Bzip2 compress the utf-8 byte representation of the string and return the compressed data as base64.
crypt.Charset = "utf-8"
crypt.EncodingMode = "base64"
Dim compressedStr As String = crypt.CompressStringENC(sb.GetAsString())

Debug.WriteLine(compressedStr)

' Result: 4aeUs+4CAABCWmgzMUFZJlNZZ6znBgAAfNeAABJABQBAAIAmZJwAIABwUNNMAAUqoekYjMp4ixF1FlFxF8i5i1FvFwizF9iwi9RdxaizF7RZi6i0ixF3Fui/i7kinChIM9ZzgwA=

' The result contains an 8-byte header composed of a 4-byte magic number (0xB394A7E1) and a 4-byte length.
' Do the following to BZip2 decompress using Chilkat Compression
Dim bd As New Chilkat.BinData
bd.AppendEncoded(compressedStr,"base64")

' Remove the 8-byte header.
bd.RemoveChunk(0,8)

' Decompress
Dim compress As New Chilkat.Compression
compress.Algorithm = "bzip2"
compress.DecompressBd(bd)

' Get the decompressed string.
Dim decompressedStr As String = bd.GetString("utf-8")
Debug.WriteLine(decompressedStr)