flutter pub add charcode基于插件公开信息、社区数据与项目使用情况整理的选型参考。
charcode 包提供了 ASCII 和常见非 ASCII 字符代码的整数常量，方便访问字符代码点。它包含诸如 'a'、'A'、'0' 以及 '@' 和 '€' 等符号的命名常量，使在处理字符编码时代码更具可读性和可维护性。非常适合需要直接引用代码点的解析、字符串操作和低级别文本处理任务。该包轻量且兼容所有主要平台。
以下为关联源码仓库的 README 原文快照，最新内容请访问源码仓库。
This package can generate constant symbolic names for character codes.
The constants can used when working directly with characters as integers,
to make the code more readable: if (firstChar == $A) ... vs
if (firstChar == 0x41 /*A*/).
The package also provides a set of pre-defined constants covering all ASCII characters and all HTML entities.
Those constants are intended for use while developing a new package or application. When development is done, it's recommended that you generate a file for yourself, containing only the constants that you actually use, and include that in your project.
To generate a set of constants, run the charcode application with a list
of the characters you want to reference.
Example:
dart run charcode -o lib/src/charcodes.dart "09.e\-ftn{}[],:"
Run dart run charcode --help to see other options.
After switching to the generated constants file, you can, and should, remove your dependency on this package, or keep it as a dev-dependency in case you want to generate the file again.
To use the pre-defined constants, import either the ASCII or the HTML library
import "package:charcode/ascii.dart";
// or
import "package:charcode/html_entity.dart";
or import both libraries using the combined charcode.dart library:
import "package:charcode/charcode.dart";
(Importing both libraries directly causes some conflicting names to be inaccessible.)
The character names are preceded by a $ to avoid conflicting with other
variables, due to their short and common names (for example "$i").
Characters that are valid in a Dart identifier directly follow the $.
Examples: $_, $a, $B and $3. Other characters are given symbolic names.
The names of letters are lower-case for lower-case letters ($sigma for σ),
and mixed- or upper-case for upper-case letters ($Sigma for Σ).
The names of symbols and punctuation are all lower-case or camelCase,
and omit suffixes like "sign", "symbol" and "mark".
Examples: $plus, $exclamation, $tilde, $doubleQuote.
The ascii.dart library defines a symbolic name for each ASCII character.
Some characters have more than one name. For example the common name $tab
and the official abbreviation $ht for the horizontal tab.
The html_entity.dart library defines a constant for each HTML 4.01 character
entity using their standard entity abbreviation, including case.
Examples: $nbsp for &nbps;, $aring for the lower-case å
and $Aring for the upper-case Å.
The HTML entities include all characters in the Latin-1 code page, Greek letters and some mathematical symbols.
The charcode.dart library exports both ascii.dart and
html_entity.dart. Where both libraries define the same name,
the HTML entity name is preferred.
The Dart language doesn't have character literals. If that ever changes, this package will become irrelevant. Until then, this package can be used for the most common characters. See request for character literals.