@47ng/codec 中文文档教程

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@47ng/codec

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Uint8Array 在浏览器和 Node.js 中从/到 UTF-8、base64url 和 hex 的通用转换

Features

可用

• utf8 - UTF-8
• b64 - Base 64 URL (RFC-4648, Section 5)
• hex - Hexadecimal, lowercase
• Simple conversion between string representation
• Encoding detection

的编解码器：当心！ utf8 使用与其他编解码器不同的约定（编码和解码 被交换），以反映 TextEncoder 和 TextDecoder 的行为。

Installation

$ yarn add @47ng/codec
# or
$ npm i @47ng/codec

Support

• Node.js: >=11.x
• Browser: See caniuse for TextEncoder / TextDecoder

Examples

import { b64, hex, utf8 } from '@47ng/codec'

b64.encode(utf8.encode('Hello, World !')) // SGVsbG8sIFdvcmxkICE=
hex.encode(b64.decode('SGVsbG8sIFdvcmxkICE=')) // 48656c6c6f2c20576f726c642021
utf8.decode(hex.decode('48656c6c6f2c20576f726c642021')) // Hello, World !

b64.decode('SGVsbG8sIFdvcmxkICE=') // <Buffer 48 65 6c 6c 6f 2c 20 57 6f 72 6c 64 20 21>

Documentation

UTF-8

• utf8.encode: Convert an UTF-8 string into an array of bytes (Uint8Array)
• utf8.decode: Convert an array of bytes into an UTF-8 string

示例：

import { utf8 } from '@47ng/codec'

const uint8Array = utf8.encode('Hello, World!')
// Uint8Array [72, 101, 108, 108, 111, 44, 32, 87, 111, 114, 108, 100, 33]

const backToText = utf8.decode(uint8Array)
// 'Hello, World!'

Base 64

• b64.encode: Convert an array of bytes into a base64url string
• b64.decode: Convert a base64 string into an array of bytes
• b64.urlSafe: Convert a standard base64 string to base64url
• b64.urlUnsafe: Convert a base64url string to standard base64 dictionary

注意：对于解码，支持任何字典，尾部填充（=）是可选的。

示例：

import { b64, utf8 } from '@47ng/codec'

const uint8Array = b64.decode('8J-Ri_CfjI0')
// Uint8Array [240, 159, 145, 139, 240, 159, 140, 141]

// Encoding always emits padding
const backToBase64 = b64.encode(uint8Array)
// '8J-Ri_CfjI0='

const asText = utf8.decode(uint8Array)
// '????????'

Hex

• hex.encode: Convert an array of bytes into a hex string
• hex.decode: Convert a hex string into an array of bytes

注意：解码接受任何大小写（小写、大写、混合）。

示例：

import { hex } from '@47ng/codec'

const uint8Array = hex.decode('48656C6C6F2C20576f726c642021')
// Uint8Array [72, 101, 108, 108, 111, 44, 32, 87, 111, 114, 108, 100, 33]

// Encoding is always lowercase
const backToBase64 = hex.encode(uint8Array)
// '48656c6c6f2c20576f726c642021'

Utilities

该库导出用于从一个字符串转换的便捷方法 对另一个表示：

import {
  hexToBase64url,
  base64ToHex,
  utf8ToBase64,
  base64toUTF8,
  utf8ToHex,
  hexToUTF8
} from '@47ng/codec'

base64ToHex('SGVsbG8sIFdvcmxkICE=')
// 48656c6c6f2c20576f726c642021

hexToBase64url('48656c6c6f2c20576f726c642021')
// SGVsbG8sIFdvcmxkICE=

utf8ToBase64('Hello, World !')
// SGVsbG8sIFdvcmxkICE=

base64toUTF8('SGVsbG8sIFdvcmxkICE=')
// Hello, World !

utf8ToHex('Hello, World !')
// 48656c6c6f2c20576f726c642021

hexToUTF8('48656c6c6f2c20576f726c642021')
// Hello, World !

它还导出具有强 TypeScript 类型的编码器/解码器对象，以帮助您 构建您自己的编码器 & 解码器：

import { encoders, decoders, Encoding } from '@47ng/codec'

// type Encoding = 'base64' | 'utf8' | 'hex'

function convert(
  input: string,
  inputEncoding: Encoding,
  outputEncoding: Encoding
): string {
  const decoder = decoders[inputEncoding]
  const encoder = encoders[outputEncoding]
  return encoder(decoder(input))
}

convert('Hello, World!', 'utf8', 'base64')
// SGVsbG8sIFdvcmxkICE

convert('Hello, World!', 'utf8', 'hex')
// 48656c6c6f2c20576f726c642021

您可以检测字符串的编码：

import { detectEncoding } from '@47ng/codec'

detectEncoding('baadf00dcafebabe') // hex

// Both variants of base64 are detected
detectEncoding('SGVs+G8s/FdvcmxkICE=') // base64
detectEncoding('SGVs-G8s_FdvcmxkICE=') // base64

detectEncoding('not hex not base64') // utf8

License

MIT - 用 ❤️ 制作 弗朗索瓦·贝斯特。

在工作中使用这个包？ 赞助我以帮助支持和维护。