PureBasic

Compress Text Feed to Binary

See more Compression Examples

This example receives incoming text data in chunks, compresses as a stream, and accumulates the compressed binary data. PureBasic

IncludeFile "CkBinData.pb"
IncludeFile "CkStringBuilder.pb"
IncludeFile "CkCompression.pb"

Procedure ChilkatExample()

    success.i = 0

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

    bdCompressed.i = CkBinData::ckCreate()
    If bdCompressed.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    compress.i = CkCompression::ckCreate()
    If compress.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkCompression::setCkAlgorithm(compress, "deflate")
    CkCompression::setCkCharset(compress, "utf-8")

    sbUncompressedChunk.i = CkStringBuilder::ckCreate()
    If sbUncompressedChunk.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkCompression::setCkFirstChunk(compress, 1)
    CkCompression::setCkLastChunk(compress, 0)

    i.i
    For i = 0 To 24
        If i = 24
            CkCompression::setCkLastChunk(compress, 1)
        EndIf

        CkStringBuilder::ckClear(sbUncompressedChunk)
        CkStringBuilder::ckAppendInt(sbUncompressedChunk,i)
        CkStringBuilder::ckAppend(sbUncompressedChunk,": This is a line of data to be compressed..." + Chr(13) + Chr(10))

        CkCompression::ckCompressSb(compress,sbUncompressedChunk,bdCompressed)

        CkCompression::setCkFirstChunk(compress, 0)
    Next

    ; Show the compressed data in hex format:
    Debug "The hex encoded compressed text:"
    Debug CkBinData::ckGetEncoded(bdCompressed,"hex")

    ; Now decompress in one call.  It is important to set both FirstChunk and LastChunk = 1
    bdDecompressed.i = CkBinData::ckCreate()
    If bdDecompressed.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkCompression::setCkFirstChunk(compress, 1)
    CkCompression::setCkLastChunk(compress, 1)
    success = CkCompression::ckDecompressBd2(compress,bdCompressed,bdDecompressed)
    If success = 0
        Debug CkCompression::ckLastErrorText(compress)
        CkBinData::ckDispose(bdCompressed)
        CkCompression::ckDispose(compress)
        CkStringBuilder::ckDispose(sbUncompressedChunk)
        CkBinData::ckDispose(bdDecompressed)
        ProcedureReturn
    EndIf

    originalText.s = CkBinData::ckGetString(bdDecompressed,"utf-8")
    Debug originalText


    CkBinData::ckDispose(bdCompressed)
    CkCompression::ckDispose(compress)
    CkStringBuilder::ckDispose(sbUncompressedChunk)
    CkBinData::ckDispose(bdDecompressed)


    ProcedureReturn
EndProcedure