(Chilkat2-Python) Transition from BeginCompressStringENC to FirstChunk/LastChunk

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

Note: This example requires Chilkat v11.0.0 or greater.

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import chilkat2

success = False

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

sbCompressedBase64 = chilkat2.StringBuilder()

compress = chilkat2.Compression()
compress.Algorithm = "deflate"
compress.Charset = "utf-8"
compress.EncodingMode = "base64"

sbIndex = chilkat2.StringBuilder()

# ----------------------------------------------------------------------------------
# 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.FirstChunk = True
compress.LastChunk = False

bdCompressed = chilkat2.BinData()
sbUncompressedChunk = chilkat2.StringBuilder()

for i in range(0,25):
    if (i == 24):
        compress.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.FirstChunk = False

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

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