CkPython

Transition from BeginCompressStringENC to FirstChunk/LastChunk

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

import chilkat

success = False

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

sbCompressedBase64 = chilkat.CkStringBuilder()

compress = chilkat.CkCompression()
compress.put_Algorithm("deflate")
compress.put_Charset("utf-8")
compress.put_EncodingMode("base64")

sbIndex = chilkat.CkStringBuilder()

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

for i in range(0,25):
    # 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.
    sbIndex.Clear()
    sbIndex.AppendInt(i)
    if (i == 0):
        sbCompressedBase64.Append(compress.beginCompressStringENC(sbIndex.getAsString()))
    else:
        sbCompressedBase64.Append(compress.moreCompressStringENC(sbIndex.getAsString()))

    sbCompressedBase64.Append(compress.moreCompressStringENC(": This is a line of data to be compressed...\r\n"))

# Flush any remaining output.
sbCompressedBase64.Append(compress.endCompressStringENC())

print("The base64 encoded compressed text:")
print(sbCompressedBase64.getAsString())

# Decompress in one call:
originalText = compress.decompressStringENC(sbCompressedBase64.getAsString())
print(originalText)

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

sbCompressedBase64.Clear()

compress.put_FirstChunk(True)
compress.put_LastChunk(False)

bdCompressed = chilkat.CkBinData()
sbUncompressedChunk = chilkat.CkStringBuilder()

for i in range(0,25):
    if (i == 24):
        compress.put_LastChunk(True)

    sbUncompressedChunk.Clear()
    sbUncompressedChunk.AppendInt(i)
    sbUncompressedChunk.Append(": This is a line of data to be compressed...\r\n")

    compress.CompressSb(sbUncompressedChunk,bdCompressed)

    compress.put_FirstChunk(False)

print("The base64 encoded compressed text:")
print(bdCompressed.getEncoded("base64"))

# Decompress in one call:
originalText = compress.decompressStringENC(bdCompressed.getEncoded("base64"))
print(originalText)