Page 150 - JavaScript

Convert an ArrayBuffer or typed array to a Blob

var array = new Uint8Array([0x04, 0x06, 0x07, 0x08]);

var blob = new Blob([array]);

Manipulating ArrayBuffers with DataViews

DataViews provide methods to read and write individual values from an ArrayBuffer, instead of
viewing the entire thing as an array of a single type. Here we set two bytes individually then
interpret them together as a 16-bit unsigned integer, first big-endian then little-endian.

var buffer = new ArrayBuffer(2);
var view = new DataView(buffer);

view.setUint8(0, 0xFF);
view.setUint8(1, 0x01);

console.log(view.getUint16(0, false)); // 65281
console.log(view.getUint16(0, true)); // 511

Creating a TypedArray from a Base64 string

var data =
'iVBORw0KGgoAAAANSUhEUgAAAAUAAAAFCAYAAACN' +
'byblAAAAHElEQVQI12P4//8/w38GIAXDIBKE0DHx' +
'gljNBAAO9TXL0Y4OHwAAAABJRU5ErkJggg==';

var characters = atob(data);

var array = new Uint8Array(characters.length);

for (var i = 0; i < characters.length; i++) {
array[i] = characters.charCodeAt(i);
}

Using TypedArrays

TypedArrays are a set of types providing different views into fixed-length mutable binary
ArrayBuffers. For the most part, they act like Arrays that coerce all assigned values to a given
numeric type. You can pass an ArrayBuffer instance to a TypedArray constructor to create a new
view of its data.

var buffer = new ArrayBuffer(8);
var byteView = new Uint8Array(buffer);
var floatView = new Float64Array(buffer);

console.log(byteView); // [0, 0, 0, 0, 0, 0, 0, 0]
console.log(floatView); // [0]
byteView[0] = 0x01;
byteView[1] = 0x02;
byteView[2] = 0x04;

https://riptutorial.com/ 107