ZipCrc Ruby Reference Documentation

CkZipCrc

Current Version: 10.1.2

Calculate a Zip CRC checksum for a file or in-memory data.

Object Creation

obj = Chilkat::CkZipCrc.new()

Properties

DebugLogFilePath
# strVal is a string
# ckStr is a CkString
zipCrc.get_DebugLogFilePath(ckStr);
strVal = zipCrc.debugLogFilePath();
zipCrc.put_DebugLogFilePath(strVal);

If set to a file path, this property logs the LastErrorText of each Chilkat method or property call to the specified file. This logging helps identify the context and history of Chilkat calls leading up to any crash or hang, aiding in debugging.

Enabling the VerboseLogging property provides more detailed information. This property is mainly used for debugging rare instances where a Chilkat method call causes a hang or crash, which should generally not happen.

Possible causes of hangs include:

  • A timeout property set to 0, indicating an infinite timeout.
  • A hang occurring within an event callback in the application code.
  • An internal bug in the Chilkat code causing the hang.

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LastErrorHtml
# strVal is a string
# ckStr is a CkString
zipCrc.get_LastErrorHtml(ckStr);
strVal = zipCrc.lastErrorHtml();

Provides HTML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.

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LastErrorText
# strVal is a string
# ckStr is a CkString
zipCrc.get_LastErrorText(ckStr);
strVal = zipCrc.lastErrorText();

Provides plain text information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.

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LastErrorXml
# strVal is a string
# ckStr is a CkString
zipCrc.get_LastErrorXml(ckStr);
strVal = zipCrc.lastErrorXml();

Provides XML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.

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LastMethodSuccess
# boolVal is a boolean
boolVal = zipCrc.get_LastMethodSuccess();
zipCrc.put_LastMethodSuccess(boolVal);

Indicates the success or failure of the most recent method call: true means success, false means failure. This property remains unchanged by property setters or getters. This method is present to address challenges in checking for null or Nothing returns in certain programming languages.

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Utf8
# boolVal is a boolean
boolVal = zipCrc.get_Utf8();
zipCrc.put_Utf8(boolVal);

When set to true, all "const char *" arguments are interpreted as utf-8 strings. If set to false (the default), then "const char *" arguments are interpreted as ANSI strings. Also, when set to true, and Chilkat method returning a "const char *" is returning the utf-8 representation. If set to false, all "const char *" return values are ANSI strings.

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VerboseLogging
# boolVal is a boolean
boolVal = zipCrc.get_VerboseLogging();
zipCrc.put_VerboseLogging(boolVal);

If set to true, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is false. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.

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Version
# strVal is a string
# ckStr is a CkString
zipCrc.get_Version(ckStr);
strVal = zipCrc.version();

Version of the component/library, such as "10.1.0"

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Methods

BeginStream
zipCrc.BeginStream();

Provides a way to calculate a CRC by streaming the data a chunk at a time. An application would start by calling BeginStream. Then it would add data by calling MoreData for each additional chunk. After the last chunk has been processed, the EndStream method is called to return the CRC.

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CalculateCrc
# data is a CkByteData
retInt = zipCrc.CalculateCrc(data);

Calculates a 32-bit CRC for in-memory byte data. This is the 32-bit CRC that would be found in a Zip file header if a file containing the data was added to a zip archive. Returns the CRC32 of the data.

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CrcBd
# bd is a CkBinData
retInt = zipCrc.CrcBd(bd);
Introduced in version 9.5.0.75

Calculates a CRC32 for the bytes contained in bd.

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CrcSb
# sb is a CkStringBuilder
# charset is a string
retInt = zipCrc.CrcSb(sb, charset);
Introduced in version 9.5.0.75

Calculates a CRC32 for the string contained in sb. The charset is the byte representation to be used for the sb when calculating the CRC32. It can be utf-8, utf-16, windows-1252, iso-8859-1, or any of the character encodings (charsets) listed at the link below.

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CrcString
# str is a string
# charset is a string
retInt = zipCrc.CrcString(str, charset);
Introduced in version 9.5.0.75

Calculates a CRC32 for a string. The charset is the byte representation to be used for the str when calculating the CRC32. It can be utf-8, utf-16, windows-1252, iso-8859-1, or any of the character encodings (charsets) listed at the link below.

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EndStream
retInt = zipCrc.EndStream();

Finalizes and returns the Zip CRC value calculated by calling BeginStream followed by multiple calls to MoreData.

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FileCrc
# path is a string
retInt = zipCrc.FileCrc(path);

Calculates the CRC32 of a file. The data contained in the file is streamed for the calculation to keep the memory footprint small and constant. Returns the CRC32 of the file.

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FileCrcAsync (1)
# returns a CkTask
# path is a string
ret_task = zipCrc.FileCrcAsync(path);

Creates an asynchronous task to call the FileCrc method with the arguments provided.

Returns nil on failure

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LoadTaskCaller
# task is a CkTask
status = zipCrc.LoadTaskCaller(task);
Introduced in version 9.5.0.80

Loads the caller of the task's async method.

Returns true for success, false for failure.

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MoreData
# data is a CkByteData
zipCrc.MoreData(data);

Adds additional data to the CRC currently being calculated. (See BeginStream for more information.)

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ToHex
# crc is an integer
# outStr is a CkString (output)
status = zipCrc.ToHex(crc, outStr);
retStr = zipCrc.toHex(crc);

Converts a 32-bit integer to a hex string.

Returns true for success, false for failure.

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