(DataFlex) Compress Text Feed to Binary

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

The purpose is to demonstrate the BeginCompressString, MoreCompressString, and EndCompressString methods.

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

Use ChilkatAx-win32.pkg

Procedure Test
    Boolean iSuccess
    Handle hoCompressedData
    Variant hoCompressedBytes
    Handle hoCompress
    Handle hoSbIndex
    Integer i
    String sOriginalText
    String sTemp1

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

    Get Create (RefClass(cComChilkatBinData)) To hoCompressedData
    If (Not(IsComObjectCreated(hoCompressedData))) Begin
        Send CreateComObject of hoCompressedData
    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"

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

    For i From 0 To 24
        // Note: It is possible (and normal) for a BeginCompress* or MoreCompress* method to return
        // an empty string (or 0 bytes).  When this happens, the input data is not lost.  It will be flushed
        // in a subsequent call.
        Send ComClear To hoSbIndex
        Get ComAppendInt Of hoSbIndex i To iSuccess
        If (i = 0) Begin
            Get ComGetAsString Of hoSbIndex To sTemp1
            Get ComBeginCompressString Of hoCompress sTemp1 To hoCompressedBytes
        End
        Else Begin
            Get ComGetAsString Of hoSbIndex To sTemp1
            Get ComMoreCompressString Of hoCompress sTemp1 To hoCompressedBytes
        End

        Get ComAppendBinary Of hoCompressedData vCompressedBytes To iSuccess
        Get ComMoreCompressString Of hoCompress ": This is a line of data to be compressed..." + (character(13)) + (character(10)) To hoCompressedBytes
        Get ComAppendBinary Of hoCompressedData vCompressedBytes To iSuccess
    Loop

    // Flush any remaining output.
    Get ComEndCompressString Of hoCompress To hoCompressedBytes
    Get ComAppendBinary Of hoCompressedData vCompressedBytes To iSuccess

    // Show the compressed data in hex format:
    Showln "The hex encoded compressed text:"
    Get ComGetEncoded Of hoCompressedData "hex" To sTemp1
    Showln sTemp1

    // Now decompress in one call:
    Get ComGetBinary Of hoCompressedData To hoCompressedBytes
    Get ComDecompressString Of hoCompress vCompressedBytes To sOriginalText
    Showln sOriginalText


End_Procedure