flutter pub add html_character_entities根據套件公開資料產生的選型評估，僅供參考。
一個 Flutter/Dart 工具套件，提供 HTML 4.01 字元實體的完整對應，包含 ASCII 和十六進位代碼。它提供方法以這些實體編碼和解碼字串，確保在網頁內容中準確處理特殊字元。適合從事 HTML 文字處理、呈現或資料交換且需精確字元編碼的開發者。此套件支援所有主要平台，並提供清楚的原始碼存取。
以下為關聯原始碼儲存庫的 README 原文快照，最新內容請造訪原始碼儲存庫。
A Dart utility class containing maps of key/value pairs for every HTML 4.01 character entity, including ASCII and hex codes, and methods to encode and decode strings to and from those character entities.
import 'package:html_character_entities/html_character_entities.dart';
The decode method accepts a string as an argument and returns it after
replacing every character entity with their corresponding characters.
String string = 'An ampersand can be written as & and &.';
print(HtmlCharacterEntities.decode(string)); // An ampersand can be written as & and &.
The encode() method has an argument, [characters], that accepts a string
of all characters that should be encoded. It defaults to the 5 reserved
characters in both HTML and XML: less-than (<), greater-than (>),
ampersand (&), apostrophe or single quote ('), and double-quote (").
String string = '<, >, &, \', and " aren\'t safe to use in HTML and XML.';
print(HtmlCharacterEntities.encode(string));
// <, >, &, ', and " aren't safe to use in HTML and XML.
print(HtmlCharacterEntities.encode(string, characters: 'XHTML'));
// <, >, &, ', and " aren't safe to use in HTML and XML.
If [characters] is null, every character in the HtmlCharacterEntities.characters map will be encoded.
A map of every HTML 4.01 character code, as well as their ASCII and hex
code entities can be referenced from HtmlCharacterEntities.characters.
Note: The hex codes in the map don't have leading 0s. I.e. the hex
code ¥ is in the map as ¥. When decoding hex code
entities, the leading 0s will be removed by the parser before being
looked up.
Map<String, String> c = HtmlCharacterEntities.characters;
String string = 'There are 4 suites of cards: ${c['♠']} Spades, ${c['♣']} Clubs, ${c['♥']} Hearts, ${c['♦']} Diamonds';
print(string); // There are 4 suites of cards: ♠ Spades, ♣ Clubs, ♥ Hearts, ♦ Diamonds
Maps containing the characters with their respective character codes
as values can also be referenced. They are used by the encode method.
// A map with only ASCII code character entities as values.
Map<String, String> ascii = HtmlCharacterEntities.asciiCodes;
// A map with all non-ASCII code character entities as values.
Map<String, String> entity = HtmlCharacterEntities.entities;
String string = '< and > exist as both ASCII codes (${ascii['<']} and ${ascii['>']}) and character entities (${entity['<']} and ${entity['>']}).';
print(string); // < and > exist as both ASCII codes (< and >) and character entities (< and >).