Bz2 Xbase++ Reference Documentation
Bz2
Current Version: 11.6.0
Chilkat.Bz2 provides BZip2 compression and decompression for files, memory buffers, and BinData. It can create standard .bz2 file images, decompress .bz2 content back to its original bytes, and support abortable long-running operations.
For an extended overview, see Bz2 Class Overview
Object Creation
LOCAL oBz2
oBz2 := CreateObject("Chilkat.Bz2")
// ... use oBz2 ...
oBz2:destroy()Xbase++ uses the Chilkat ActiveX through the automation object returned by CreateObject(); properties and methods are accessed with the send operator (oHttp:ConnectTimeout := 30, oHttp:Download(cUrl, cPath)), and :destroy() releases the object. Register the Chilkat ActiveX matching the bitness of your Xbase++ application. To bind to a specific major version of Chilkat, append the major version number to the ProgID, such as CreateObject("Chilkat.Bz2.11") for Chilkat v11.*.*.
Boolean properties, arguments and return values are integers in the ActiveX: pass 1 or 0, and test a method's success with == 1. A method that fails to return an object returns NIL. Objects returned by methods (such as an HttpResponse or JsonObject) are automation objects too and should likewise be released with :destroy(). Methods and properties that pass or return raw byte arrays are not shown on this page; use the BinData-based alternatives (methods ending in Bd) or the base64 / hex string-encoded variants instead.
Properties
AbortCurrent
Set this property to 1
A synchronous call can be cancelled by setting this property from another thread. After cancellation is processed, Chilkat resets the property to 0
LastErrorText to determine the final outcome.DebugLogFilePath
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.
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.
topLastErrorText
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.
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.
topLastMethodSuccess
Indicates the success or failure of the most recent method call: 1 means success, 0 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. Note: This property does not apply to methods that return integer values or to boolean-returning methods where the boolean does not indicate success or failure.
LastStringResult
In SQL Server stored procedures, this property holds the string return value of the most recent method call that returns a string. It is accessible only when Chilkat.Global.KeepStringResult is set to TRUE. SQL Server has limitations on string lengths returned from methods and properties, but temp tables can be used to access large strings.
LastStringResultLen
The length, in characters, of the string contained in the LastStringResult property.
topVerboseLogging
If set to 1, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is 0. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.
Version
Methods
CompressBd
Compresses the current contents of bd in place. On success, the BinData no longer contains the original bytes; it contains the complete standard BZip2 stream that may be saved with a .bz2 extension.
Returns 1 for success, 0 for failure.
topCompressBdAsync (1)
Creates an asynchronous task to call the CompressBd method with the arguments provided.
Returns NIL on failure
CompressFile
Reads the file at inFilename and writes its compressed bytes as a standard BZip2 stream to the file at toPath. The output is conventionally given a .bz2 extension.
Both arguments must identify files, not directories. They may be absolute or relative paths, for example data/report.txt and data/report.txt.bz2.
.bz2 file represents one compressed byte stream. It does not store the original filename, directory path, timestamps, permissions, or multiple archive entries. Formats such as .tar.bz2 first combine files in a TAR archive and then compress that TAR stream with BZip2.Returns 1 for success, 0 for failure.
CompressFileAsync (1)
Creates an asynchronous task to call the CompressFile method with the arguments provided.
Returns NIL on failure
LoadTaskCaller
Loads this Bz2 object with the caller state associated with the asynchronous operation represented by task.
Task created by a compatible Bz2 asynchronous method; an unrelated task cannot be loaded.Returns 1 for success, 0 for failure.
topUncompressBd
Decompresses the BZip2 stream currently contained in bd in place. On success, the BinData is replaced with the original uncompressed bytes.
bd must contain a complete, valid BZip2 stream, such as the bytes of a .bz2 file or the output of CompressBd. This method operates on binary data and does not perform character-set conversion.Returns 1 for success, 0 for failure.
topUncompressBdAsync (1)
Creates an asynchronous task to call the UncompressBd method with the arguments provided.
Returns NIL on failure
UncompressFile
Reads the BZip2 stream from the file at inFilename, decompresses it, and writes the original uncompressed bytes to the file at toPath.
Both arguments must identify files, not directories. Chilkat does not derive the destination name from the .bz2 filename because the BZip2 stream does not contain the original filename.
.bz2 file normally contains a single compressed byte stream rather than a collection of named files.Returns 1 for success, 0 for failure.
topUncompressFileAsync (1)
Creates an asynchronous task to call the UncompressFile method with the arguments provided.
Returns NIL on failure