TypedArray & ArrayBuffer & DataView All In One

bit & byte

1 Byte === 8 Bits

1 字节 === 8 位 (比特位)

const buffer = new ArrayBuffer(8);
const view = new Int32Array(buffer);


// create a TypedArray with a size in bytes
const typedArray1 = new Int8Array(8);
typedArray1[0] = 32;

// 复制，初始化
const typedArray2 = new Int8Array(typedArray1);
typedArray2[1] = 42;

console.log(typedArray1);
// Int8Array [32, 0, 0, 0, 0, 0, 0, 0]

console.log(typedArray2);
// Int8Array [32, 42, 0, 0, 0, 0, 0, 0]

const buffer = new ArrayBuffer(16);
const view = new DataView(buffer, 0);

view.setInt16(1, 42);
view.getInt16(1);
// 42

js no for loop 100 array

js no for generate 100 length array with each index as value


const arr = new Uint8Array(100); 
// new in ES2017

// Uint8Array(100) [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]

old_arr = new Array(100);
// (100) [empty × 100]


// no for & create Array 100

const arr = new Uint8Array(100).map((item, i) => i);

// Uint8Array(100) [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99]

https://www.cnblogs.com/xgqfrms/p/13034475.html

https://www.cnblogs.com/xgqfrms/p/8982974.html