charset_codec library

Cross-platform character encoding codecs aligned with CPython behavior.

Provides encoding and decoding, strict validation, asynchronous processing, and bounded incremental processing across Dart VM, Flutter, and Web.

Classes

CharsetCodec

Encodes, decodes, and creates incremental processors for one charset. Obtain instances through the top-level codec function and reuse them across calls. Codec tables are loaded on demand.

CodecInfo

Describes a codec resolved by this package.

IncrementalDecoder

Decodes a byte stream while retaining only bounded codec state.

IncrementalEncoder

Encodes a text stream while retaining only bounded codec state.

Enums

CodecErrorMode

Selects how malformed input or unrepresentable text is handled.

CodecOperation

The conversion direction associated with a CodecException.

Properties

supportedPythonCodecNames → Iterable<String>

All normalized CPython codec names supported by this package.

no setter

Functions

codec(String encoding) → CharsetCodec

Resolves encoding to a codec using its canonical name or a common alias.

decodeBytes(List<int> bytes, {required String encoding, CodecErrorMode errors = CodecErrorMode.strict}) → String

Decodes bytes with encoding.

decodeBytesAsync(List<int> bytes, {required String encoding, CodecErrorMode errors = CodecErrorMode.strict}) → Future<String>

Asynchronously decodes bytes with encoding.

encodeString(String text, {required String encoding, CodecErrorMode errors = CodecErrorMode.strict}) → Uint8List

Encodes text with encoding and returns a new byte buffer.

encodeStringAsync(String text, {required String encoding, CodecErrorMode errors = CodecErrorMode.strict}) → Future<Uint8List>

Asynchronously encodes text with encoding.

isValidDataForEncoding(List<int> data, String encoding) → bool

Whether data is completely valid for encoding in strict mode.

isValidDataForEncodingAsync(List<int> data, String encoding) → Future<bool>

Asynchronously checks whether data is strictly valid for encoding.

lookupCodecInfo(String encoding) → CodecInfo?

Looks up metadata for encoding, accepting canonical names and aliases.

tryDecodeBytes(List<int> bytes, {required String encoding, CodecErrorMode errors = CodecErrorMode.strict}) → String?

Tries to decode bytes with encoding, returning null on any failure.

tryEncodeString(String text, {required String encoding, CodecErrorMode errors = CodecErrorMode.strict}) → Uint8List?

Tries to encode text with encoding, returning null on any failure.

Exceptions / Errors

CodecException

A structured codec lookup or conversion failure. Contains the encoding name, operation, error position, and readable reason for display or logging by callers.