---
product: Chilkat
product_version: 11.7.0
language: python
language_label: Python
class: Gzip
license: bundle
deprecated: false
reference_html: https://www.chilkatsoft.com/refdoc/pythonGzipRef.html
---
# Chilkat Gzip — Python — v11.7.0

> Chilkat 11.7.0 · language=python · class=Gzip
> Other versions: replace `11.7.0` in this URL. Other languages: `https://www.chilkatsoft.com/ai-docs/v/11.7.0/<lang>/classes/Gzip.md`.
> Language-wide rules (install, unlock, error model, strings/bytes): `https://www.chilkatsoft.com/ai-docs/v/11.7.0/python/guide.md`.

## Purpose

**Compress, decompress, inspect, and convert GZIP data in files or memory.**

`Chilkat.Gzip` provides GZIP compression and decompression for file-based and in-memory workflows. It can compress and uncompress files, strings, byte arrays, `BinData`, and encoded data such as Base64 or hex. It also supports `.tar.gz` extraction, gzip metadata such as original filename, timestamp, and comments, and inspection of GZIP header information without fully expanding the compressed data.

**File compression**

Compress files to `.gz`, uncompress `.gz` files, and write decompressed output directly to disk.

**Memory-based data**

Work with byte arrays and `Chilkat.BinData` for applications that need compression or decompression without temporary files.

**String workflows**

Compress and uncompress strings with explicit charset handling for text data that must round-trip correctly.

**Encoded GZIP data**

Handle GZIP data represented as Base64, hex, or other supported encoded forms when binary data must be carried as text.

**GZIP metadata**

Set or inspect metadata such as original filename, modified time, comments, and extra data stored in the GZIP header.

**Tar-gzip and XFDL**

Extract `.tar.gz` archives and decode XFDL content that uses gzip-related encodings.

**Common pattern:** Use `Gzip` when the data is a single GZIP stream, a `.gz` file, or a `.tar.gz` archive. For ZIP archives, use `Chilkat.Zip`; for raw deflate or zlib-style compression, use `Chilkat.Compression`.

For an extended overview, see [Gzip Class Overview](https://www.chilkatsoft.com/gzip_overview.asp).

## Object creation, unlocking and error handling

**Object Creation**

```python
obj = chilkat2.Gzip()
```

Call `Global.UnlockBundle` once at the start of the program, before using this or any other Chilkat class. Any string unlocks a fully functional 30-day trial; a purchased unlock code is used in production. See `guide.md` for the exact code in Python.

Minimal complete program:

```python
import chilkat2

# Required once per process. Any string unlocks a 30-day trial; use your purchased code in production.
glob = chilkat2.Global()
if not glob.UnlockBundle("Anything for 30-day trial"):
    print(glob.LastErrorText)
    raise SystemExit(1)

gzip = chilkat2.Gzip()

success = gzip.CompressFile("<srcPath>", "<destPath>")
if not success:
    print(gzip.LastErrorText)   # full diagnostic of what went wrong
    raise SystemExit(1)
```

How failure is reported depends on the method's return type and is stated in the note under each method below. In every case the diagnostic text is in the `LastErrorText` property of the object whose method was called.

## Members common to every Chilkat class

Documented once per language in `common-members.md`; listed here so this page is self-contained.

| Property | Signature | Access | Meaning |
|---|---|---|---|
| `DebugLogFilePath` | `string DebugLogFilePath` | read/write | If set to a file path, this property logs the LastErrorText of each Chilkat method or property call to the specified file. |
| `LastErrorHtml` | `string LastErrorHtml (read-only)` | read-only | Provides HTML-formatted information about the last called method or property. |
| `LastErrorText` | `string LastErrorText (read-only)` | read-only | Provides plain text information about the last called method or property. |
| `LastErrorXml` | `string LastErrorXml (read-only)` | read-only | Provides XML-formatted information about the last called method or property. |
| `LastMethodSuccess` | `bool LastMethodSuccess` | read/write | Indicates the success or failure of the most recent method call: `True` means success, `False` means failure. |
| `VerboseLogging` | `bool VerboseLogging` | read/write | If set to `True`, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. |
| `Version` | `string Version (read-only)` | read-only | Version of the component/library, such as "10.1.0" |

## Member index

| Member | Kind | Signature |
|---|---|---|
| `AbortCurrent` | property, read/write | `bool AbortCurrent` |
| `Comment` | property, read/write | `string Comment` |
| `CompressionLevel` | property, read/write | `int CompressionLevel` |
| `ExtraData` | property, read/write | `memoryview ExtraData` |
| `Filename` | property, read/write | `string Filename` |
| `LastModStr` | property, read/write | `string LastModStr` |
| `UseCurrentDate` | property, read/write | `bool UseCurrentDate` |
| `CompressBd` | method | `bool CompressBd(BinData binDat)` |
| `CompressFile` | method | `bool CompressFile(string srcPath, string destPath)` |
| `CompressFile2` | method | `bool CompressFile2(string srcPath, string embeddedFilename, string destPath)` |
| `CompressFileBd` | method | `bool CompressFileBd(string filePath, BinData bd)` |
| `CompressFileToMem` | method | `memoryview CompressFileToMem(string inFilename)` |
| `CompressMemory` | method | `memoryview CompressMemory(memoryview inData)` |
| `CompressMemToFile` | method | `bool CompressMemToFile(memoryview inData, string destPath)` |
| `CompressSb` | method | `bool CompressSb(StringBuilder sb, string charset, BinData bd)` |
| `CompressString` | method | `memoryview CompressString(string inStr, string destCharset)` |
| `CompressStringENC` | method | `string CompressStringENC(string inStr, string charset, string encoding)` |
| `CompressStringToFile` | method | `bool CompressStringToFile(string inStr, string destCharset, string destPath)` |
| `GetGzipInfo` | method | `bool GetGzipInfo(string filePath, JsonObject json)` |
| `GetGzipInfoBd` | method | `bool GetGzipInfoBd(BinData bd, JsonObject json)` |
| `IsGzip` | method | `bool IsGzip(BinData bd)` |
| `LoadTaskCaller` | method | `bool LoadTaskCaller(Task task)` |
| `SetDt` | method | `bool SetDt(CkDateTime dt)` |
| `SetExtraData` | method | `bool SetExtraData(string encodedData, string encoding)` |
| `UncompressBd` | method | `bool UncompressBd(BinData binDat)` |
| `UncompressBdToFile` | method | `bool UncompressBdToFile(BinData bd, string filePath)` |
| `UncompressFile` | method | `bool UncompressFile(string srcPath, string destPath)` |
| `UncompressFileToMem` | method | `memoryview UncompressFileToMem(string srcPath)` |
| `UncompressFileToString` | method | `string UncompressFileToString(string srcPath, string charset)` |
| `UncompressMemory` | method | `memoryview UncompressMemory(memoryview inData)` |
| `UncompressMemToFile` | method | `bool UncompressMemToFile(memoryview inData, string destPath)` |
| `UncompressString` | method | `string UncompressString(memoryview inData, string inCharset)` |
| `UncompressStringENC` | method | `string UncompressStringENC(string inStr, string charset, string encoding)` |
| `UnTarGz` | method | `bool UnTarGz(string gzPath, string destDir, bool bNoAbsolute)` |
| `XfdlToXml` | method | `string XfdlToXml(string xfldData)` |

Deprecated members are listed at the end of this file with their replacements; do not use them in new code.

## Properties

### Gzip.AbortCurrent

`Chilkat 11.7.0 · python · Gzip · AbortCurrent · property · read/write · since 9.5.0.58`

```python
bool AbortCurrent
```

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.

### Gzip.Comment

`Chilkat 11.7.0 · python · Gzip · Comment · property · read/write`

```python
string Comment
```

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

### Gzip.CompressionLevel

`Chilkat 11.7.0 · python · Gzip · CompressionLevel · property · read/write · since 9.5.0.50`

```python
int CompressionLevel
```

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.

### Gzip.ExtraData

`Chilkat 11.7.0 · python · Gzip · ExtraData · property · read/write`

```python
memoryview ExtraData
```

Optional binary data to include in the Gzip header when a `Compress*` method is called.

### Gzip.Filename

`Chilkat 11.7.0 · python · Gzip · Filename · property · read/write`

```python
string Filename
```

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.

### Gzip.LastModStr

`Chilkat 11.7.0 · python · Gzip · LastModStr · property · read/write`

```python
string LastModStr
```

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.

### Gzip.UseCurrentDate

`Chilkat 11.7.0 · python · Gzip · UseCurrentDate · property · read/write`

```python
bool UseCurrentDate
```

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.

## Methods

### Gzip.CompressBd

`Chilkat 11.7.0 · python · Gzip · CompressBd · method · since 9.5.0.67`

```python
bool CompressBd(BinData binDat)
```

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

Returns True for success, False for failure.

Async variant: `CompressBdAsync` — same arguments, returns a `Task` (see Async variants below).

### Gzip.CompressFile

`Chilkat 11.7.0 · python · Gzip · CompressFile · method`

```python
bool CompressFile(string srcPath, string destPath)
```

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

Returns True for success, False for failure.

Async variant: `CompressFileAsync` — same arguments, returns a `Task` (see Async variants below).

### Gzip.CompressFile2

`Chilkat 11.7.0 · python · Gzip · CompressFile2 · method`

```python
bool CompressFile2(string srcPath, string embeddedFilename, string destPath)
```

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.

Async variant: `CompressFile2Async` — same arguments, returns a `Task` (see Async variants below).

### Gzip.CompressFileBd

`Chilkat 11.7.0 · python · Gzip · CompressFileBd · method · since 11.0.0`

```python
bool CompressFileBd(string filePath, BinData bd)
```

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.

Async variant: `CompressFileBdAsync` — same arguments, returns a `Task` (see Async variants below).

### Gzip.CompressFileToMem

`Chilkat 11.7.0 · python · Gzip · CompressFileToMem · method`

```python
memoryview CompressFileToMem(string inFilename)
```

Compresses a file and returns the resulting Gzip data as a byte array.

The compressed output is held in memory and has a maximum size limit of 4 GB.

Returns an empty (zero-length) memoryview on failure. Check the `LastMethodSuccess` property to determine success or failure.

Async variant: `CompressFileToMemAsync` — same arguments, returns a `Task` (see Async variants below).

### Gzip.CompressMemory

`Chilkat 11.7.0 · python · Gzip · CompressMemory · method`

```python
memoryview CompressMemory(memoryview inData)
```

Compresses a byte array and returns the result as an in-memory Gzip image.

The uncompressed input data must not exceed 4 GB.

Returns an empty (zero-length) memoryview on failure. Check the `LastMethodSuccess` property to determine success or failure.

Async variant: `CompressMemoryAsync` — same arguments, returns a `Task` (see Async variants below).

### Gzip.CompressMemToFile

`Chilkat 11.7.0 · python · Gzip · CompressMemToFile · method`

```python
bool CompressMemToFile(memoryview inData, string destPath)
```

Compresses a byte array and writes the resulting Gzip data to a file.

Returns True for success, False for failure.

Async variant: `CompressMemToFileAsync` — same arguments, returns a `Task` (see Async variants below).

### Gzip.CompressSb

`Chilkat 11.7.0 · python · Gzip · CompressSb · method · since 11.0.0`

```python
bool CompressSb(StringBuilder sb, string charset, BinData bd)
```

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.

Async variant: `CompressSbAsync` — same arguments, returns a `Task` (see Async variants below).

### Gzip.CompressString

`Chilkat 11.7.0 · python · Gzip · CompressString · method`

```python
memoryview CompressString(string inStr, string destCharset)
```

**Full documentation for this method (same in every language):** [Full List of Charset Names](https://www.chilkatsoft.com/ai-docs/v/11.7.0/articles/charsets_supported_by_chilkat.md)

Compresses a string and returns the Gzip-compressed data as a byte array.

The string is first converted to bytes using the character set specified by `destCharset`. Common values include `utf-8`, `iso-8859-1`, and `shift_JIS`.

Returns an empty (zero-length) memoryview on failure. Check the `LastMethodSuccess` property to determine success or failure.

Async variant: `CompressStringAsync` — same arguments, returns a `Task` (see Async variants below).

### Gzip.CompressStringENC

`Chilkat 11.7.0 · python · Gzip · CompressStringENC · method`

```python
string CompressStringENC(string inStr, string charset, string encoding)
```

**Full documentation for this method (same in every language):** [Binary Encodings Supported by Chilkat](https://www.chilkatsoft.com/ai-docs/v/11.7.0/articles/binary_encodings.md)

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 an empty string on failure. Check the `LastMethodSuccess` property to determine success or failure.

### Gzip.CompressStringToFile

`Chilkat 11.7.0 · python · Gzip · CompressStringToFile · method`

```python
bool CompressStringToFile(string inStr, string destCharset, string destPath)
```

**Full documentation for this method (same in every language):** [Full List of Charset Names](https://www.chilkatsoft.com/ai-docs/v/11.7.0/articles/charsets_supported_by_chilkat.md)

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.

Async variant: `CompressStringToFileAsync` — same arguments, returns a `Task` (see Async variants below).

### Gzip.GetGzipInfo

`Chilkat 11.7.0 · python · Gzip · GetGzipInfo · method · since 11.5.0`

```python
bool GetGzipInfo(string filePath, JsonObject json)
```

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.

### Gzip.GetGzipInfoBd

`Chilkat 11.7.0 · python · Gzip · GetGzipInfoBd · method · since 11.5.0`

```python
bool GetGzipInfoBd(BinData bd, JsonObject json)
```

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.

### Gzip.IsGzip

`Chilkat 11.7.0 · python · Gzip · IsGzip · method · since 11.0.0`

```python
bool IsGzip(BinData bd)
```

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

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

### Gzip.LoadTaskCaller

`Chilkat 11.7.0 · python · Gzip · LoadTaskCaller · method · since 9.5.0.80`

```python
bool LoadTaskCaller(Task task)
```

Loads the caller of the task's async method.

Returns True for success, False for failure.

### Gzip.SetDt

`Chilkat 11.7.0 · python · Gzip · SetDt · method`

```python
bool SetDt(CkDateTime dt)
```

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.

### Gzip.SetExtraData

`Chilkat 11.7.0 · python · Gzip · SetExtraData · method · since 11.0.0`

```python
bool SetExtraData(string encodedData, string encoding)
```

**Full documentation for this method (same in every language):** [Binary Encodings Supported by Chilkat](https://www.chilkatsoft.com/ai-docs/v/11.7.0/articles/binary_encodings.md)

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.

### Gzip.UncompressBd

`Chilkat 11.7.0 · python · Gzip · UncompressBd · method · since 9.5.0.67`

```python
bool UncompressBd(BinData binDat)
```

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.

Async variant: `UncompressBdAsync` — same arguments, returns a `Task` (see Async variants below).

### Gzip.UncompressBdToFile

`Chilkat 11.7.0 · python · Gzip · UncompressBdToFile · method · since 11.0.0`

```python
bool UncompressBdToFile(BinData bd, string filePath)
```

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

Returns True for success, False for failure.

Async variant: `UncompressBdToFileAsync` — same arguments, returns a `Task` (see Async variants below).

### Gzip.UncompressFile

`Chilkat 11.7.0 · python · Gzip · UncompressFile · method`

```python
bool UncompressFile(string srcPath, string destPath)
```

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.

Async variant: `UncompressFileAsync` — same arguments, returns a `Task` (see Async variants below).

### Gzip.UncompressFileToMem

`Chilkat 11.7.0 · python · Gzip · UncompressFileToMem · method`

```python
memoryview UncompressFileToMem(string srcPath)
```

Decompresses a Gzip file and returns the uncompressed data as a byte array.

The uncompressed output is held in memory and must not exceed 4 GB.

Returns an empty (zero-length) memoryview on failure. Check the `LastMethodSuccess` property to determine success or failure.

Async variant: `UncompressFileToMemAsync` — same arguments, returns a `Task` (see Async variants below).

### Gzip.UncompressFileToString

`Chilkat 11.7.0 · python · Gzip · UncompressFileToString · method`

```python
string UncompressFileToString(string srcPath, string charset)
```

**Full documentation for this method (same in every language):** [List of Valid Charsets](https://www.chilkatsoft.com/ai-docs/v/11.7.0/articles/charsets_supported_by_chilkat.md)

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 an empty string on failure. Check the `LastMethodSuccess` property to determine success or failure.

Async variant: `UncompressFileToStringAsync` — same arguments, returns a `Task` (see Async variants below).

### Gzip.UncompressMemory

`Chilkat 11.7.0 · python · Gzip · UncompressMemory · method`

```python
memoryview UncompressMemory(memoryview inData)
```

Decompresses an in-memory Gzip image and returns the uncompressed data as a byte array.

The uncompressed output is held in memory and must not exceed 4 GB.

Returns an empty (zero-length) memoryview on failure. Check the `LastMethodSuccess` property to determine success or failure.

Async variant: `UncompressMemoryAsync` — same arguments, returns a `Task` (see Async variants below).

### Gzip.UncompressMemToFile

`Chilkat 11.7.0 · python · Gzip · UncompressMemToFile · method`

```python
bool UncompressMemToFile(memoryview inData, string destPath)
```

Decompresses an in-memory Gzip image and writes the uncompressed data to a file.

Returns True for success, False for failure.

Async variant: `UncompressMemToFileAsync` — same arguments, returns a `Task` (see Async variants below).

### Gzip.UncompressString

`Chilkat 11.7.0 · python · Gzip · UncompressString · method`

```python
string UncompressString(memoryview inData, string inCharset)
```

**Full documentation for this method (same in every language):** [Full List of Charset Names](https://www.chilkatsoft.com/ai-docs/v/11.7.0/articles/charsets_supported_by_chilkat.md)

Decompresses Gzip-compressed data and returns the result as a string.

After decompression, the result is raw binary data (a sequence of bytes). These bytes are then interpreted as text using the specified character set (such as `utf-8`, `iso-8859-1`, etc.) to produce the final string.

Internally, Chilkat converts the byte sequence to a string by interpreting the bytes according to the specified character set. For example, if `utf-8` is specified, the bytes are treated as the UTF-8 byte representation of text and decoded into the internal string format used by the programming language.

It is important that the character set matches the one originally used when the data was compressed. If the wrong character set is used, the byte-to-text conversion may produce incorrect or unreadable characters.

Returns an empty string on failure. Check the `LastMethodSuccess` property to determine success or failure.

Async variant: `UncompressStringAsync` — same arguments, returns a `Task` (see Async variants below).

### Gzip.UncompressStringENC

`Chilkat 11.7.0 · python · Gzip · UncompressStringENC · method`

```python
string UncompressStringENC(string inStr, string charset, string encoding)
```

**Full documentation for this method (same in every language):** [Binary Encodings Supported by Chilkat](https://www.chilkatsoft.com/ai-docs/v/11.7.0/articles/binary_encodings.md)

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 an empty string on failure. Check the `LastMethodSuccess` property to determine success or failure.

### Gzip.UnTarGz

`Chilkat 11.7.0 · python · Gzip · UnTarGz · method`

```python
bool UnTarGz(string gzPath, string destDir, bool bNoAbsolute)
```

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.

Async variant: `UnTarGzAsync` — same arguments, returns a `Task` (see Async variants below).

### Gzip.XfdlToXml

`Chilkat 11.7.0 · python · Gzip · XfdlToXml · method`

```python
string XfdlToXml(string xfldData)
```

**Full documentation for this method (same in every language):** [More about XFDL](https://www.chilkatsoft.com/ai-docs/v/11.7.0/articles/xfdl.md)

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 an empty string on failure. Check the `LastMethodSuccess` property to determine success or failure.

## Events and callbacks

This binding has no event callbacks. For progress, percent-done or cancellation use the `*Async` variant of a method and poll the returned `Task` (`PercentDone`, `Finished`, `Cancel`).

## Async variants

Each returns a `Task` instead of the result and takes the same arguments as the synchronous method; run the task, wait for `Finished`, then read the result from the task. No new Async methods are added from 11.7.0 on.

```python
Task CompressBdAsync(BinData binDat)
Task CompressFileAsync(string srcPath, string destPath)
Task CompressFile2Async(string srcPath, string embeddedFilename, string destPath)
Task CompressFileBdAsync(string filePath, BinData bd)
Task CompressFileToMemAsync(string inFilename)
Task CompressMemoryAsync(memoryview inData)
Task CompressMemToFileAsync(memoryview inData, string destPath)
Task CompressSbAsync(StringBuilder sb, string charset, BinData bd)
Task CompressStringAsync(string inStr, string destCharset)
Task CompressStringToFileAsync(string inStr, string destCharset, string destPath)
Task UncompressBdAsync(BinData binDat)
Task UncompressBdToFileAsync(BinData bd, string filePath)
Task UncompressFileAsync(string srcPath, string destPath)
Task UncompressFileToMemAsync(string srcPath)
Task UncompressFileToStringAsync(string srcPath, string charset)
Task UncompressMemoryAsync(memoryview inData)
Task UncompressMemToFileAsync(memoryview inData, string destPath)
Task UncompressStringAsync(memoryview inData, string inCharset)
Task UnTarGzAsync(string gzPath, string destDir, bool bNoAbsolute)
```

## Deprecated members — do not use in new code

| Member | Kind | Deprecated in | Use instead |
|---|---|---|---|
| `Decode` | method | before 11.6.1 | — |
| `DeflateStringENC` | method | before 11.6.1 | — |
| `Encode` | method | before 11.6.1 | — |
| `ExamineFile` | method | before 11.6.1 | — |
| `ExamineMemory` | method | before 11.6.1 | — |
| `GetDt` | method | before 11.6.1 | — |
| `InflateStringENC` | method | before 11.6.1 | — |
| `ReadFile` | method | before 11.6.1 | — |
| `WriteFile` | method | before 11.6.1 | — |

## Related classes

[`BinData`](https://www.chilkatsoft.com/ai-docs/v/11.7.0/python/classes/BinData.md), [`CkDateTime`](https://www.chilkatsoft.com/ai-docs/v/11.7.0/python/classes/CkDateTime.md), [`JsonObject`](https://www.chilkatsoft.com/ai-docs/v/11.7.0/python/classes/JsonObject.md), [`StringBuilder`](https://www.chilkatsoft.com/ai-docs/v/11.7.0/python/classes/StringBuilder.md), [`Task`](https://www.chilkatsoft.com/ai-docs/v/11.7.0/python/classes/Task.md)