Tcl

Transition from BeginCompressStringENC to FirstChunk/LastChunk

Provides instructions for replacing deprecated BeginCompressStringENC method calls with using FirstChunk/LastChunk properties. Tcl

load ./chilkat.dll

set success 0

# This example assumes the Chilkat API to have been previously unlocked.
# See Global Unlock Sample 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]

# ----------------------------------------------------------------------------------
# This is the deprecated way of compressing in chunks using Begin/More/End methods..
# ----------------------------------------------------------------------------------

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 $i
    if {$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]

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

# ----------------------------------------------------------------------------------
# This is new way of compressing in chunks using FirstChunk and LastChunk properties
# ----------------------------------------------------------------------------------

CkStringBuilder_Clear $sbCompressedBase64

CkCompression_put_FirstChunk $compress 1
CkCompression_put_LastChunk $compress 0

set bdCompressed [new_CkBinData]

set sbUncompressedChunk [new_CkStringBuilder]

for {set i 0} {$i <= 24} {incr i} {
    if {$i == 24} then {
        CkCompression_put_LastChunk $compress 1
    }

    CkStringBuilder_Clear $sbUncompressedChunk
    CkStringBuilder_AppendInt $sbUncompressedChunk $i
    CkStringBuilder_Append $sbUncompressedChunk ": This is a line of data to be compressed...\r\n"

    CkCompression_CompressSb $compress $sbUncompressedChunk $bdCompressed

    CkCompression_put_FirstChunk $compress 0
}

puts "The base64 encoded compressed text:"
puts [CkBinData_getEncoded $bdCompressed base64]

# Decompress in one call:
set originalText [CkCompression_decompressStringENC $compress [CkBinData_getEncoded $bdCompressed "base64"]]
puts "$originalText"

delete_CkStringBuilder $sbCompressedBase64
delete_CkCompression $compress
delete_CkStringBuilder $sbIndex
delete_CkBinData $bdCompressed
delete_CkStringBuilder $sbUncompressedChunk