Gzip

Set this property to True to request that the currently running operation be aborted. This is useful for long-running operations such as large file compression or decompression. Methods that complete quickly are generally not affected.

If no method is currently running, the property is automatically reset to False when the next method begins. After an abort occurs, it is also reset to False. Both synchronous and asynchronous operations can be aborted. For synchronous calls, another thread must set this property.

An optional comment to embed in the Gzip file when a Compress* method is called.

Controls the compression level used when creating Gzip data. The value can range from 0 to 9.

• 0 = no compression
• 9 = maximum compression

The default value is 6, which is a typical balance between compression size and speed. Higher levels may take significantly more CPU time while producing only slightly smaller output, depending on the data.

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.

The filename to embed in the Gzip file when a Compress* method is called. Some Gzip extraction tools use this embedded filename as the default output filename.

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.

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.

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.

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. 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.

Specifies the last-modified date/time to embed in the Gzip file when a Compress* method is called.

The value must be provided as an RFC 822 formatted date/time string.

Example:

Sun, 12 Apr 2026 12:45:26 GMT

If this property is not set, the current system date/time is used automatically.

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.

The length, in characters, of the string contained in the LastStringResult property.

Controls the last-modified date/time assigned to files created by Uncompress* methods.

When set to True, the extracted file uses the current date/time instead of the date/time stored in the Gzip data.

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.

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

Compresses the contents of a BinData object in place, replacing the original data with Gzip-compressed data.

Returns True for success, False for failure.

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

Returns Null on failure

Compresses a file and writes the result as a Gzip file, typically with a .gz extension.

Returns True for success, False for failure.

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

Returns Null on failure

Compresses a file and writes the result as a Gzip file, while allowing a different filename to be embedded inside the Gzip data.

The inFilename parameter is the actual file on disk. The srcPath parameter is the filename stored in the Gzip header and may be used by extraction tools as the output filename.

Returns True for success, False for failure.

Creates an asynchronous task to call the CompressFile2 method with the arguments provided.

Returns Null on failure

Compresses a file and stores the resulting Gzip data in a BinData object.

The compressed output is held in memory. The maximum compressed size is 4 GB.

Returns True for success, False for failure.

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

Returns Null on failure

Compresses the text contained in a StringBuilder and writes the Gzip-compressed result to a BinData object.

Before compression, the string is converted to bytes using the specified character set, such as utf-8, iso-8859-1, or shift_JIS.

Returns True for success, False for failure.

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

Returns Null on failure

Compresses a string and returns the Gzip-compressed data as an encoded string.

The input string is first converted to bytes using the specified character set. The compressed binary data is then encoded using the requested encoding, such as base64, hex, url, base32, or quoted-printable.

Returns Null on failure

Compresses a string and writes the resulting Gzip data to a file.

The string is first converted to bytes using the character set specified by destCharset.

Returns True for success, False for failure.

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

Returns Null on failure

Retrieves metadata stored in a Gzip file and returns the information in a JsonObject.

The metadata is returned using the following JSON structure:

{
  "extraData": "AAECAw==",
  "filename": "example.txt",
  "comment": "This is the comment"
}

• filename – the original filename embedded in the Gzip file (if present)
• comment – an optional descriptive comment (if present)
• extraData – optional additional binary data, returned as a Base64-encoded string

Any of these fields may be omitted if they were not included when the Gzip file was created.

Returns True for success, False for failure.

Retrieves metadata stored in Gzip data contained within a BinData object and returns the information in a JsonObject.

The metadata is returned using the same JSON structure:

{
  "extraData": "AAECAw==",
  "filename": "example.txt",
  "comment": "This is the comment"
}

• filename – the original filename embedded in the Gzip data (if present)
• comment – an optional descriptive comment (if present)
• extraData – optional additional binary data, returned as a Base64-encoded string

Any of these fields may be omitted if they were not included when the Gzip data was created.

Returns True for success, False for failure.

Checks whether the data contained in a BinData object is in Gzip format.

Returns True if the data is Gzip-formatted, or False otherwise.

Loads the caller of the task's async method.

Returns True for success, False for failure.

Sets the last-modified date/time to embed in the Gzip file when a Compress* method is called.

If no date/time is explicitly set, the current system date/time is used.

Returns True for success, False for failure.

Sets optional extra binary data to include in the Gzip header when a Compress* method is called.

The data is passed as an encoded string. Supported encodings include base64, hex, ascii, and many others.

Returns True for success, False for failure.

Decompresses Gzip data contained in a BinData object in place, replacing the compressed data with the uncompressed data.

Returns True for success, False for failure.

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

Returns Null on failure

Decompresses Gzip data stored in a BinData object and writes the result to a file.

Returns True for success, False for failure.

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

Returns Null on failure

Decompresses a Gzip file and writes the result to the specified output path.

The output filename is provided by the caller. The filename embedded in the Gzip data is not used.

Returns True for success, False for failure.

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

Returns Null on failure

Decompresses a Gzip file that contains text and returns the uncompressed text as a string.

The charset parameter specifies the character encoding of the uncompressed text, such as utf-8, iso-8859-1, windows-1252, shift_JIS, big5, etc.

Returns Null on failure

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

Returns Null on failure

Decompresses Gzip data provided as an encoded string and returns the uncompressed result as text.

The input string is first decoded using the specified encoding, such as base64, hex, url, base32, quoted-printable, etc. The decoded Gzip data is then decompressed and converted to text using the specified character set.

Returns Null on failure

Extracts a .tar.gz archive to a directory.

The Gzip decompression and TAR extraction are performed in streaming mode. No temporary files are created, and memory usage remains small and constant.

If bNoAbsolute is True, absolute paths in the TAR archive are not allowed. This helps protect against extracting files to unsafe locations, such as system directories.

Returns True for success, False for failure.

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

Returns Null on failure

Converts encoded and compressed XFDL data to a decompressed XML string.

XFDL data is often stored in an ASCII-safe compressed form, such as asci-gzip or asc-gzip. Despite the name, this does not always mean the data is a standard .gz file. In some XFDL files, the compressed payload uses the raw deflate format rather than the full Gzip file format.

Chilkat automatically detects the actual encoding and compression format used by the XFDL data. It decodes the ASCII/Base64 representation, determines whether the compressed data is Gzip or deflate, decompresses it correctly, and returns the resulting XML string.

This allows applications to call XfdlToXml without needing to manually distinguish between XFDL variants such as Base64+Gzip and Base64+Deflate.

Returns the decoded and decompressed XML string.

XFDL (Extensible Forms Description Language) is an XML-based format used to define secure, interactive electronic forms—often including digital signatures and integrity protections—commonly used in government and enterprise applications.

Returns Null on failure

Compresses a string using the raw deflate algorithm and returns the compressed data as an encoded string.

The input string is first converted to bytes using the specified character set. The compressed binary data is then encoded using the requested output encoding, such as hex, base64, url, or quoted-printable.

Important: This method produces raw deflate-compressed data, not Gzip-format data. Use the Compress* methods when Gzip format output is required.

Returns Null on failure

Checks whether the specified file contains Gzip-formatted data.

Returns True if the file is in Gzip format, or False otherwise.

Applications should instead access the LastModStr property.

Gets the last-modification date/time to be embedded within the .gz.

Returns Null on failure

Decompresses data previously compressed with DeflateStringENC.

The input string is first decoded using the specified input encoding, such as hex, base64, url, or quoted-printable. The resulting compressed bytes are then inflated, and the final bytes are converted to a string using the specified character set.

Returns Null on failure