base64.js
Yet another Base64 transcoder.
Install
$ npm install --save js-base64
Usage
In Browser
Locally…
<script src="base64.js"></script>
… or Directly from CDN. In which case you don't even need to install.
<script src="https://cdn.jsdelivr.net/npm/js-base64@3.7.5/base64.min.js"></script>
This good old way loads Base64
in the global context (window
). Though Base64.noConflict()
is made available, you should consider using ES6 Module to avoid tainting window
.
As an ES6 Module
locally…
import { Base64 } from 'js-base64';
import { encode, decode } from 'js-base64';
or even remotely.
<script type="module">
import { Base64 } from 'https://cdn.jsdelivr.net/npm/js-base64@3.7.5/base64.mjs';
</script>
<script type="module">
import { encode, decode } from 'https://cdn.jsdelivr.net/npm/js-base64@3.7.5/base64.mjs';
</script>
node.js (commonjs)
const {Base64} = require('js-base64');
Unlike the case above, the global context is no longer modified.
You can also use esm to import
instead of require
.
require=require('esm')(module);
import {Base64} from 'js-base64';
SYNOPSIS
let latin = 'dankogai';
let utf8 = '小飼弾'
let u8s = new Uint8Array([100,97,110,107,111,103,97,105]);
Base64.encode(latin);
Base64.encode(latin, true);
Base64.encodeURI(latin);
Base64.btoa(latin);
Base64.btoa(utf8);
Base64.fromUint8Array(u8s);
Base64.fromUint8Array(u8s, true);
Base64.encode(utf8);
Base64.encode(utf8, true)
Base64.encodeURI(utf8);
Base64.decode( 'ZGFua29nYWk=');
Base64.decode( 'ZGFua29nYWk');
Base64.atob( 'ZGFua29nYWk=');
Base64.atob( '5bCP6aO85by+');
Base64.toUint8Array('ZGFua29nYWk=');
Base64.decode( '5bCP6aO85by+');
Base64.decode( '5bCP6aO85by-');
Base64.isValid(0);
Base64.isValid('');
Base64.isValid('ZA==');
Base64.isValid('Z A=');
Base64.isValid('ZA');
Base64.isValid('++');
Base64.isValid('--');
Base64.isValid('+-');
Built-in Extensions
By default Base64
leaves built-in prototypes untouched. But you can extend them as below.
Base64.extendString();
'dankogai'.toBase64();
'小飼弾'.toBase64();
'小飼弾'.toBase64(true);
'小飼弾'.toBase64URI();
'小飼弾'.toBase64URL();
'ZGFua29nYWk='.fromBase64();
'5bCP6aO85by+'.fromBase64();
'5bCP6aO85by-'.fromBase64();
'5bCP6aO85by-'.toUint8Array();
Base64.extendUint8Array();
u8s.toBase64();
u8s.toBase64URI();
u8s.toBase64URL();
Base64.extendBuiltins()
.decode()
vs .atob
(and .encode()
vs btoa()
)
Suppose you have:
var pngBase64 =
"iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAQAAAC1HAwCAAAAC0lEQVR42mNkYAAAAAYAAjCB0C8AAAAASUVORK5CYII=";
Which is a Base64-encoded 1x1 transparent PNG, DO NOT USE Base64.decode(pngBase64)
. Use Base64.atob(pngBase64)
instead. Base64.decode()
decodes to UTF-8 string while Base64.atob()
decodes to bytes, which is compatible to browser built-in atob()
(Which is absent in node.js). The same rule applies to the opposite direction.
Or even better, Base64.toUint8Array(pngBase64)
.
Brief History
- Since version 3.3 it is written in TypeScript. Now
base64.mjs
is compiled from base64.ts
then base64.js
is generated from base64.mjs
. - Since version 3.7
base64.js
is ES5-compatible again (hence IE11-compatible). - Since 3.0
js-base64
switch to ES2015 module so it is no longer compatible with legacy browsers like IE (see above)