【JavaScript】convert base64 to array buffer

VanillaJS

方法一

function base64ToArrayBuffer(base64) {
    var binaryString = atob(base64);
    var bytes = new Uint8Array(binaryString.length);
    for (var i = 0; i < binaryString.length; i++) {
        bytes[i] = binaryString.charCodeAt(i);
    }
    return bytes.buffer;
}

Note：atob 的 decode data 不應該含有 data:image/[<mime type>];base64,

方法二

Uint8Array.from(atob(base64_string), c => c.charCodeAt(0))

Node.js

const myBuffer = Buffer.from(someBase64String, 'base64')

參考

• Convert base64 string to ArrayBuffer
• Base64 to ArrayBuffer conversion is generating corrupted image file
• Failed to execute atob on Window
• Failed to execute ‘atob’ on ‘Window’