Lianja

Transition from BeginCompressStringENC to FirstChunk/LastChunk

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

llSuccess = .F.

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

loSbCompressedBase64 = createobject("CkStringBuilder")

loCompress = createobject("CkCompression")
loCompress.Algorithm = "deflate"
loCompress.Charset = "utf-8"
loCompress.EncodingMode = "base64"

loSbIndex = createobject("CkStringBuilder")

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

for i = 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.
    loSbIndex.Clear()
    loSbIndex.AppendInt(i)
    if (i = 0) then
        loSbCompressedBase64.Append(loCompress.BeginCompressStringENC(loSbIndex.GetAsString()))
    else
        loSbCompressedBase64.Append(loCompress.MoreCompressStringENC(loSbIndex.GetAsString()))
    endif

    loSbCompressedBase64.Append(loCompress.MoreCompressStringENC(": This is a line of data to be compressed..." + Chr(13) + Chr(10)))
next

// Flush any remaining output.
loSbCompressedBase64.Append(loCompress.EndCompressStringENC())

? "The base64 encoded compressed text:"
? loSbCompressedBase64.GetAsString()

// Decompress in one call:
lcOriginalText = loCompress.DecompressStringENC(loSbCompressedBase64.GetAsString())
? lcOriginalText

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

loSbCompressedBase64.Clear()

loCompress.FirstChunk = .T.
loCompress.LastChunk = .F.

loBdCompressed = createobject("CkBinData")
loSbUncompressedChunk = createobject("CkStringBuilder")

for i = 0 to 24
    if (i = 24) then
        loCompress.LastChunk = .T.
    endif

    loSbUncompressedChunk.Clear()
    loSbUncompressedChunk.AppendInt(i)
    loSbUncompressedChunk.Append(": This is a line of data to be compressed..." + Chr(13) + Chr(10))

    loCompress.CompressSb(loSbUncompressedChunk,loBdCompressed)

    loCompress.FirstChunk = .F.
next

? "The base64 encoded compressed text:"
? loBdCompressed.GetEncoded("base64")

// Decompress in one call:
lcOriginalText = loCompress.DecompressStringENC(loBdCompressed.GetEncoded("base64"))
? lcOriginalText


release loSbCompressedBase64
release loCompress
release loSbIndex
release loBdCompressed
release loSbUncompressedChunk