UnixCompress VB.NET WinRT Reference Documentation

UnixCompress

Current Version: 9.5.0.90

UNIX (.Z) compression component.

Object Creation

Dim obj As New Chilkat.UnixCompress()

Properties

AbortCurrent
AbortCurrent As Boolean
Introduced in version 9.5.0.58

When set to True, causes the currently running method to abort. Methods that always finish quickly (i.e.have no length file operations or network communications) are not affected. If no method is running, then this property is automatically reset to False when the next method is called. When the abort occurs, this property is reset to False. Both synchronous and asynchronous method calls can be aborted. (A synchronous method call could be aborted by setting this property from a separate thread.)

top
DebugLogFilePath
DebugLogFilePath As String

If set to a file path, causes each Chilkat method or property call to automatically append it's LastErrorText to the specified log file. The information is appended such that if a hang or crash occurs, it is possible to see the context in which the problem occurred, as well as a history of all Chilkat calls up to the point of the problem. The VerboseLogging property can be set to provide more detailed information.

This property is typically used for debugging the rare cases where a Chilkat method call hangs or generates an exception that halts program execution (i.e. crashes). A hang or crash should generally never happen. The typical causes of a hang are:

  1. a timeout related property was set to 0 to explicitly indicate that an infinite timeout is desired,
  2. the hang is actually a hang within an event callback (i.e. it is a hang within the application code), or
  3. there is an internal problem (bug) in the Chilkat code that causes the hang.

top
HeartbeatMs
HeartbeatMs As Integer

The number of milliseconds between each AbortCheck event callback. The AbortCheck callback allows an application to abort any method call prior to completion. If HeartbeatMs is 0 (the default), no AbortCheck event callbacks will fire.

top
LastErrorHtml
LastErrorHtml As String (ReadOnly)

Provides information in HTML format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.

top
LastErrorText
LastErrorText As String (ReadOnly)

Provides information in plain-text format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.

top
LastErrorXml
LastErrorXml As String (ReadOnly)

Provides information in XML format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.

top
LastMethodSuccess
LastMethodSuccess As Boolean
Introduced in version 9.5.0.52

Indicate whether the last method call succeeded or failed. A value of True indicates success, a value of False indicates failure. This property is automatically set for method calls. It is not modified by property accesses. The property is automatically set to indicate success for the following types of method calls:

  • Any method that returns a string.
  • Any method returning a Chilkat object, binary bytes, or a date/time.
  • Any method returning a standard boolean status value where success = True and failure = False.
  • Any method returning an integer where failure is defined by a return value less than zero.

Note: Methods that do not fit the above requirements will always set this property equal to True. For example, a method that returns no value (such as a "void" in C++) will technically always succeed.

top
VerboseLogging
VerboseLogging As Boolean

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.

top
Version
Version As String (ReadOnly)

Version of the component/library, such as "9.5.0.63"

top

Methods

CompressFile
<Awaitable> Function CompressFileAsyncAsync(ByVal inFilename As String, ByVal destPath As String) As IAsyncOperation(Of Boolean)

Compresses a file to create a UNIX compressed file (.Z). This compression uses the LZW (Lempel-Ziv-Welch) compression algorithm.

Returns True for success, False for failure.

top
CompressFileToMem
<Awaitable> Function CompressFileToMemAsyncAsync(ByVal inFilename As String) As IAsyncOperation(Of Byte())

Unix compresses a file to an in-memory image of a .Z file. (This compression uses the LZW (Lempel-Ziv-Welch) compression algorithm.)

Returns an empty byte array on failure

top
CompressMemory
Function CompressMemory(ByVal inData As Byte()) As Byte()

Compresses in-memory data to an in-memory image of a .Z file. (This compression uses the LZW (Lempel-Ziv-Welch) compression algorithm.)

Returns an empty byte array on failure

top
CompressMemToFile
Function CompressMemToFile(ByVal inData As Byte(), ByVal destPath As String) As Boolean

Unix compresses and creates a .Z file from in-memory data. (This compression uses the LZW (Lempel-Ziv-Welch) compression algorithm.)

Returns True for success, False for failure.

top
CompressString
Function CompressString(ByVal inStr As String, ByVal charset As String) As Byte()

Compresses a string to an in-memory image of a .Z file. Prior to compression, the string is converted to the character encoding specified by charset. The charset can be any one of a large number of character encodings, such as "utf-8", "iso-8859-1", "Windows-1252", "ucs-2", etc.

Returns an empty byte array on failure

More Information and Examples
top
CompressStringToFile
Function CompressStringToFile(ByVal inStr As String, ByVal charset As String, ByVal destPath As String) As Boolean

Unix compresses and creates a .Z file from string data. The charset specifies the character encoding used for the byte representation of the characters when compressed. The charset can be any one of a large number of character encodings, such as "utf-8", "iso-8859-1", "Windows-1252", "ucs-2", etc.

Returns True for success, False for failure.

More Information and Examples
top
UncompressFile
<Awaitable> Function UncompressFileAsyncAsync(ByVal inFilename As String, ByVal destPath As String) As IAsyncOperation(Of Boolean)

Uncompresses a .Z file. (This compression uses the LZW (Lempel-Ziv-Welch) compression algorithm.)

Returns True for success, False for failure.

top
UncompressFileToMem
<Awaitable> Function UncompressFileToMemAsyncAsync(ByVal inFilename As String) As IAsyncOperation(Of Byte())

Uncompresses a .Z file directly to memory. (This compression uses the LZW (Lempel-Ziv-Welch) compression algorithm.)

Returns an empty byte array on failure

top
UncompressFileToString
<Awaitable> Function UncompressFileToStringAsyncAsync(ByVal zFilename As String, ByVal charset As String) As IAsyncOperation(Of String)

Uncompresses a .Z file that contains a text file. The contents of the text file are returned as a string. The character encoding of the text file is specified by charset. Typical charsets are "iso-8859-1", "utf-8", "windows-1252", "shift_JIS", "big5", etc.

Returns Nothing on failure

More Information and Examples
top
UncompressMemory
Function UncompressMemory(ByVal inData As Byte()) As Byte()

Uncompresses from an in-memory image of a .Z file directly into memory. (This compression uses the LZW (Lempel-Ziv-Welch) compression algorithm.)

Returns an empty byte array on failure

top
UncompressMemToFile
Function UncompressMemToFile(ByVal inData As Byte(), ByVal destPath As String) As Boolean

Uncompresses from an in-memory image of a .Z file to a file. (This compression uses the LZW (Lempel-Ziv-Welch) compression algorithm.)

Returns True for success, False for failure.

top
UncompressString
Function UncompressString(ByVal inCompressedData As Byte(), ByVal charset As String) As String

Uncompresses from an in-memory image of a .Z file directly to a string. The charset specifies the character encoding used to interpret the bytes resulting from the decompression. The charset can be any one of a large number of character encodings, such as "utf-8", "iso-8859-1", "Windows-1252", "ucs-2", etc.

Returns Nothing on failure

More Information and Examples
top
UnTarZ
<Awaitable> Function UnTarZAsyncAsync(ByVal zFilename As String, ByVal destDir As String, ByVal bNoAbsolute As Boolean) As IAsyncOperation(Of Boolean)

Unpacks a .tar.Z file. The decompress and untar occur in streaming mode. There are no temporary files and the memory footprint is constant (and small) while untarring.

Returns True for success, False for failure.

top

Events