(VBScript) Compress and Decompress Base64

Imagine we have data represented as a base64 string. This example demonstrates how to decode, compress, and re-encode to smaller base64 representing the compressed data.

Note: This example requires Chilkat v9.5.0.66 or greater.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

Dim fso, outFile
Set fso = CreateObject("Scripting.FileSystemObject")
'Create a Unicode (utf-16) output text file.
Set outFile = fso.CreateTextFile("output.txt", True, True)

' This example assumes the Chilkat API to have been previously unlocked.
' See Global Unlock Sample for sample code.

strBase64 = "VGhlIHF1aWNrIGJyb3duIGZveCBqdW1wZWQgb3ZlciB0aGUgbGF6eSBkb2cuDQpUaGUgcXVpY2sgYnJvd24gZm94IGp1bXBlZCBvdmVyIHRoZSBsYXp5IGRvZy4NClRoZSBxdWljayBicm93biBmb3gganVtcGVkIG92ZXIgdGhlIGxhenkgZG9nLg0KVGhlIHF1aWNrIGJyb3duIGZveCBqdW1wZWQgb3ZlciB0aGUgbGF6eSBkb2cuDQpUaGUgcXVpY2sgYnJvd24gZm94IGp1bXBlZCBvdmVyIHRoZSBsYXp5IGRvZy4NCg0K"

' For versions of Chilkat < 10.0.0, use CreateObject("Chilkat_9_5_0.Compression")
set compress = CreateObject("Chilkat.Compression")
compress.Algorithm = "deflate"

' For versions of Chilkat < 10.0.0, use CreateObject("Chilkat_9_5_0.BinData")
set binDat = CreateObject("Chilkat.BinData")
' Load the base64 data into a BinData object.
' This decodes the base64. The decoded bytes will be contained in the BinData.
success = binDat.AppendEncoded(strBase64,"base64")

' Compress the BinData.
success = compress.CompressBd(binDat)

' Get the compressed data in base64 format:
compressedBase64 = binDat.GetEncoded("base64")
outFile.WriteLine("compressed base64:")
outFile.WriteLine(compressedBase64)

' The compressed base64 is: C8lIVSgszUzOVkgqyi/PU0jLr1DIKs0tSE1RyC9LLVIoAcrnJFZVKqTkp+vxcoUMYeW8XAA=

' Now decompress:
success = binDat.Clear()
success = binDat.AppendEncoded(compressedBase64,"base64")
success = compress.DecompressBd(binDat)

decompressedBase64 = binDat.GetEncoded("base64")
outFile.WriteLine("decompressed base64:")
outFile.WriteLine(decompressedBase64)

' The output is the original data:
' VGhlIHF1aWNrIGJyb3duIGZveCBqdW1wZWQgb3ZlciB0aGUgbGF6eSBkb2cuDQpUaGUgcXVpY2sgYnJvd24gZm94IGp1bXBlZCBvdmVyIHRoZSBsYXp5IGRvZy4NClRoZSBxdWljayBicm93biBmb3gganVtcGVkIG92ZXIgdGhlIGxhenkgZG9nLg0KVGhlIHF1aWNrIGJyb3duIGZveCBqdW1wZWQgb3ZlciB0aGUgbGF6eSBkb2cuDQpUaGUgcXVpY2sgYnJvd24gZm94IGp1bXBlZCBvdmVyIHRoZSBsYXp5IGRvZy4NCg0K

outFile.Close