DataFlex

Compress String Feed to Base64

See more Compression Examples

This example receives incoming text data in chunks, compresses as a stream, and accumulates the compressed data in base64. DataFlex

Use ChilkatAx-win32.pkg

Procedure Test
    Boolean iSuccess
    Handle hoSbCompressedBase64
    Handle hoCompress
    Variant vBdCompressed
    Handle hoBdCompressed
    Variant vSbUncompressedChunk
    Handle hoSbUncompressedChunk
    Integer i
    String sOriginalText
    String sTemp1

    Move False To iSuccess

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

    Get Create (RefClass(cComChilkatStringBuilder)) To hoSbCompressedBase64
    If (Not(IsComObjectCreated(hoSbCompressedBase64))) Begin
        Send CreateComObject of hoSbCompressedBase64
    End

    Get Create (RefClass(cComChilkatCompression)) To hoCompress
    If (Not(IsComObjectCreated(hoCompress))) Begin
        Send CreateComObject of hoCompress
    End
    Set ComAlgorithm Of hoCompress To "deflate"
    Set ComCharset Of hoCompress To "utf-8"
    Set ComEncodingMode Of hoCompress To "base64"

    Set ComFirstChunk Of hoCompress To True
    Set ComLastChunk Of hoCompress To False

    Get Create (RefClass(cComChilkatBinData)) To hoBdCompressed
    If (Not(IsComObjectCreated(hoBdCompressed))) Begin
        Send CreateComObject of hoBdCompressed
    End
    Get Create (RefClass(cComChilkatStringBuilder)) To hoSbUncompressedChunk
    If (Not(IsComObjectCreated(hoSbUncompressedChunk))) Begin
        Send CreateComObject of hoSbUncompressedChunk
    End

    For i From 0 To 24
        If (i = 24) Begin
            Set ComLastChunk Of hoCompress To True
        End

        Send ComClear To hoSbUncompressedChunk
        Get ComAppendInt Of hoSbUncompressedChunk i To iSuccess
        Get ComAppend Of hoSbUncompressedChunk ": This is a line of data to be compressed..." + (character(13)) + (character(10)) To iSuccess

        Get pvComObject of hoSbUncompressedChunk to vSbUncompressedChunk
        Get pvComObject of hoBdCompressed to vBdCompressed
        Get ComCompressSb Of hoCompress vSbUncompressedChunk vBdCompressed To iSuccess

        Set ComFirstChunk Of hoCompress To False
    Loop

    Showln "The base64 encoded compressed text:"
    Get ComGetEncoded Of hoBdCompressed "base64" To sTemp1
    Showln sTemp1

    // Decompress in one call:
    Get ComGetEncoded Of hoBdCompressed "base64" To sTemp1
    Get ComDecompressStringENC Of hoCompress sTemp1 To sOriginalText
    Showln sOriginalText


End_Procedure