(Tcl) Compress String Feed to Base64

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

The purpose is to demonstrate the BeginCompressStringENC, MoreCompressStringENC, and EndCompressStringENC methods.

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load ./chilkat.dll

#  This example requires the Chilkat API to have been previously unlocked.
#  See Compression UnlockComponent for sample code.

set sbCompressedBase64 [new_CkStringBuilder]

set compress [new_CkCompression]

CkCompression_put_Algorithm $compress "deflate"
CkCompression_put_Charset $compress "utf-8"
CkCompression_put_EncodingMode $compress "base64"

set sbIndex [new_CkStringBuilder]

for {set i 0} {$i <= 24} {incr i} {
    #  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.
    [CkStringBuilder_Clear $sbIndex]
    [CkStringBuilder_AppendInt $sbIndex $i]
    if {[expr $i == 0]} then {
        [CkStringBuilder_Append $sbCompressedBase64 [CkCompression_beginCompressStringENC $compress [CkStringBuilder_getAsString $sbIndex]]]
    }     else {
        [CkStringBuilder_Append $sbCompressedBase64 [CkCompression_moreCompressStringENC $compress [CkStringBuilder_getAsString $sbIndex]]]
    }

    [CkStringBuilder_Append $sbCompressedBase64 [CkCompression_moreCompressStringENC $compress ": This is a line of data to be compressed...\r\n"]]
}

#  Flush any remaining output.
CkStringBuilder_Append $sbCompressedBase64 [CkCompression_endCompressStringENC $compress]

puts "The base64 encoded compressed text:"
puts [CkStringBuilder_getAsString $sbCompressedBase64]

#  Now decompress in one call:
set originalText [CkCompression_decompressStringENC $compress [CkStringBuilder_getAsString $sbCompressedBase64]]
puts "$originalText"

delete_CkStringBuilder $sbCompressedBase64
delete_CkCompression $compress
delete_CkStringBuilder $sbIndex