函数b64_to_utf8(STR) { 返回decodeURIComponent(逃避(窗口。Atob (STR))); ｝

https://developer.mozilla.org/en-US/docs/Web/API/WindowBase64/Base64_encoding_and_decoding#The_.22Unicode_Problem.22

函数b64_to_utf8(STR) { 返回decodeURIComponent(逃避(窗口。Atob (STR))); ｝

https://developer.mozilla.org/en-US/docs/Web/API/WindowBase64/Base64_encoding_and_decoding#The_.22Unicode_Problem.22

现代浏览器有内置的javascript函数用于Base64编码btoa()和解码atob()。有关旧版本浏览器支持的更多信息:https://caniuse.com/?search=atob

但是，请注意atob和btoa函数仅适用于ASCII字符集。 如果你需要Base64函数的UTF-8字符集，你可以这样做:

function base64_encode(s) {      
    return btoa(unescape(encodeURIComponent(s)));
}
function base64_decode(s) {      
    return decodeURIComponent(escape(atob(s)));
}

Internet Explorer 10+

// Define the string
var string = 'Hello World!';

// Encode the String
var encodedString = btoa(string);
console.log(encodedString); // Outputs: "SGVsbG8gV29ybGQh"

// Decode the String
var decodedString = atob(encodedString);
console.log(decodedString); // Outputs: "Hello World!"

跨浏览器

重写和模块化的UTF-8和Base64 Javascript编码和解码库/模块，用于AMD, CommonJS, Nodejs和浏览器。跨浏览器兼容的。

用node . js

下面是在Node.js中如何将普通文本编码为base64:

//Buffer() requires a number, array or string as the first parameter, and an optional encoding type as the second parameter. 
// Default is utf8, possible encoding types are ascii, utf8, ucs2, base64, binary, and hex
var b = Buffer.from('JavaScript');
// If we don't use toString(), JavaScript assumes we want to convert the object to utf8.
// We can make it convert to other formats by passing the encoding type to toString().
var s = b.toString('base64');

下面是解码base64编码字符串的方法:

var b = Buffer.from('SmF2YVNjcmlwdA==', 'base64')
var s = b.toString();

. js和

使用dojox.encoding.base64对字节数组进行编码:

var str = dojox.encoding.base64.encode(myByteArray);

解码base64编码的字符串:

var bytes = dojox.encoding.base64.decode(str)

安装angular-base64

<script src="bower_components/angular-base64/angular-base64.js"></script>

angular
    .module('myApp', ['base64'])
    .controller('myController', [

    '$base64', '$scope', 
    function($base64, $scope) {
    
        $scope.encoded = $base64.encode('a string');
        $scope.decoded = $base64.decode('YSBzdHJpbmc=');
}]);

但如何?

如果你想了解更多关于base64是如何编码的，特别是在JavaScript中，我推荐这篇文章:JavaScript中的计算机科学:base64编码

前端:上面的解决方案很好，但后端很快……

NodeJS -不弃用

使用Buffer.from。

> inBase64 = Buffer.from('plain').toString('base64')
'cGxhaW4='

> // DEPRECATED //
> new Buffer(inBase64, 'base64').toString()
'plain'
> (node:1188987) [DEP0005] DeprecationWarning: Buffer() is deprecated due to security and usability issues. Please use the Buffer.alloc(), Buffer.allocUnsafe(), or Buffer.from() methods instead.
(Use `node --trace-deprecation ...` to show where the warning was created)

// Works //
> Buffer.from(inBase64, 'base64').toString()
'plain'

在基于Gecko/ webkit的浏览器(Firefox、Chrome和Safari)和Opera中，可以使用btoa()和atob()。

原来的答案:如何在JavaScript中将字符串编码为Base64 ?