Hangul

This package is an utility to manipulate korean hangul characters (한글) in dart.

Install

$ dart pub add hangul

Getting Started

The library is composed of 2 modules:

• HangulSyllable: to validate and create hangul syllables from jamos and to destruct syllables into jamos.
• HangulInput: to create hangul sentences from input string in order to emulate keyboard strokes.

HangulSyllable

The basics of the library is to manipulate hangul syllables.

A hangul syllable is composed of 3 jamos:

• A "cho" jamo that is the first consonant.
• A "jung" jamo that is the vowel
• An optional "jong" jamo that is the last consonant.

Note that "double" characters such as ᅯ, ㅉ or ㅄ are considered as jamos.

Split a syllable into 2 or 3 jamos

HangulSyllable.fromString will split a given hangul syllable and return an instance of HangulSyllable.

It throws if the given string is not a valid syllable.

import 'package:hangul/hangul.dart';

final syllable = HangulSyllable.fromString('쪲');

syllable.cho == 'ㅉ'; // true
syllable.jung == 'ㅖ'; // true
syllable.jong == 'ㅄ'; // true

Assemble 2 or 3 jamos into a single syllable

HangulSyllable constructor allows to instantiate a syllable from 3 valid jamos.

It throws if one of the given string is not a valid jamo (order for cho, jung and jong matters).

import 'package:hangul/hangul.dart';

final syllable = HangulSyllable('ㅉ', 'ㅖ', 'ㅄ');

syllable.tostring() == '쪲'; // true

The following will throw:

import 'package:hangul/hangul.dart';

HangulSyllable('ㅆ', 'a');

// thrown AssertionError with message "Invalid character provided for jung."

HangulInput

The class HangulInput will simulate the behavior of keyboard strokes. The goal is to make it possible to implement virtual keyboards. It can also be used to combine a string of jamos together into a string of syllables.

import 'package:hangul/hangul.dart';

final input = HangulInput('');

input.pushCharacter('ㄷ');
input.pushCharacter('ㅏ');
input.pushCharacter('ㄹ');
input.pushCharacter('ㄱ');
input.pushCharacter('ㅇ');
input.pushCharacter('ㅡ');
input.pushCharacter('ㄴ');

print(input.text); // "닭은"

input.backspace();
print(input.text); // "닭ㅇ"

input.backspace();
input.backspace();
print(input.text); // "달"

// empty
input.clear();
print(input.text); // ""

utilities

import 'package:hangul/hangul.dart';

// check jamo
isValidJamo('ㄱ');  // true
isValidCho('ㄱ');  // true
isValidJung('ㅏ'); // true
isValidJong('ㄱ'); // true
isValidJong('ㅄ'); // true
isValidCho('ㅏ');  // false
isValidCho('ㅄ');  // false

// can also be used from character code
isValidJamoCode('ㄱ'.codeUnitAt(0));  // true
isValidChoCode('ㄱ'.codeUnitAt(0));  // true
isValidJungCode('ㅏ'.codeUnitAt(0)); // true
isValidJongCode('ㄱ'.codeUnitAt(0)); // true

// check syllable
isHangulSyllable('쪲');   // true
isHangulSyllable('쪲가'); // false
isHangulSyllable('ㄱ');   // false
isHangulSyllable('q');   // false

// can also be used from character code
isHangulSyllableCode('쪲'.codeUnitAt(0));   // true

// check that ends with a jong character
syllableHasJong('하');    // false
syllableHasJong('은');    // true
syllableHasJong('a');    // false

// can also be used from character code
syllableCodeHasJong('하'.codeUnitAt(0));    // false
syllableCodeHasJong('은'.codeUnitAt(0));    // true
syllableCodeHasJong('a'.codeUnitAt(0));    // false


// list of valid cho jung and jong are also exported:
final Set allJamos = {...choJamos, ...jungJamos, ...jongJamos};