pr0gramista/charset_converter

Charset converter

pub package Checks status

Encode and decode charsets using platform built-in converter. This saves app package size as you don't need any external charset maps or whole libraries like iconv. This package doesn't even contain any Dart dependencies. However this comes with the dependency on the platform.

This package was originally made to help deal with this StackOverflow question and Dart's lack of support for many specific charset like GBK, Big5, Windows-125X or ISO-8859-XX.

Usage

Checkout these snippets or full example.

Encoding

Uint8List encoded = await CharsetConverter.encode("windows1250", "Polish has óśćł");

Decoding

String decoded = await CharsetConverter.decode("windows1250",
    Uint8List.fromList([0x43, 0x7A, 0x65, 0x9C, 0xE6])); // Hello (Cześć) in Polish

Getting list of available charsets

Helpful if you don't know exact name of the charset.

List<String> charsets = await CharsetConverter.availableCharsets();

Warning: Please note that even if charset is not present on the list, it still might work. This is because the function is not returning the full list of aliases, this is presented in the example of iOS - TIS620 does not appear on the list, but ISO 8859-11, which is actually an alias of TIS620 does. To check if charset is available use CharsetConverter.checkAvailability.

Please also note that names are platform specific and may be different.

Checking availability of charset

bool isAvailable = await CharsetConverter.checkAvailability("EUC-KR");

Preview of what encoding you may find

This can be helpful if you are not sure what you are looking for.

• Android
• iOS
• Windows
• Linux

How does it work?

Android comes with Java runtime, which has a built-in Charset class which has convenient encode and decode methods. All it's left to do is use channels to pass the data.

iOS can also work with charsets with CoreFoundation CFString functions fe. CFStringConvertIANACharSetNameToEncoding. We can also easily encode and decode Strings with init and data. It is a little bit cumbersome since we have to convert the values and use ported C API.

Windows can use MultiByteToWideChar and WideCharToMultiByte from Win32.

Linux can use libIconv in GLib. Since Flutter for Linux use GTK, it is pretty suitable. However, it accept a NUL terminated UTF-8 string (like C string end with\0), so in Dart side, String will be dealt by transferring into Uint8List, and add 0 at the end.

Contributing

Feel free to create issues, fix bugs, add new functionalities even if you are not sure about. Everyone is welcome!

See also

• flutter_charset_detector for detecting text encoding