The Uint8Array() constructor creates Uint8Array objects. The contents are initialized to 0.
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Uint8Array() constructor
Syntax
js
new Uint8Array()
new Uint8Array(length)
new Uint8Array(typedArray)
new Uint8Array(object)
new Uint8Array(buffer)
new Uint8Array(buffer, byteOffset)
new Uint8Array(buffer, byteOffset, length)
Parameters
See TypedArray.
Exceptions
See TypedArray.
Examples
Different ways to create a Uint8Array
js
// From a length
const uint8 = new Uint8Array(2);
uint8[0] = 42;
console.log(uint8[0]); // 42
console.log(uint8.length); // 2
console.log(uint8.BYTES_PER_ELEMENT); // 1
// From an array
const x = new Uint8Array([21, 31]);
console.log(x[1]); // 31
// From another TypedArray
const y = new Uint8Array(x);
console.log(y[0]); // 21
// From an ArrayBuffer
const buffer = new ArrayBuffer(8);
const z = new Uint8Array(buffer, 1, 4);
console.log(z.byteOffset); // 1
// From an iterable
const iterable = (function* () {
yield* [1, 2, 3];
})();
const uint8FromIterable = new Uint8Array(iterable);
console.log(uint8FromIterable);
// Uint8Array [1, 2, 3]
Specifications
Browser compatibility
| Desktop | Mobile | Server | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | Deno | Node.js | ||
Uint8Array |
7 | 12 | 4 | 11.6 | 5.1 | 18 | 4 | 12 | 4.2 | 1.0 | 4 | 1.0 | 0.10.0 | |
constructor_without_parameters |
7 | 12 | 55 | 11.6 | 5.1 | 18 | 55 | 12 | 5 | 1.0 | ≤37 | 1.0 | 0.10.0 | |
iterable_allowed |
39 | 14 | 52 | 26 | 10 | 39 | 52 | 26 | 10 | 4.0 | 39 | 1.0 | 4.0.0 | |
new_required |
7 | 14 | 44 | 15 | 5.1 | 18 | 44 | 14 | 5 | 1.0 | ≤37 | 1.0 | 0.12.0 | |
See also
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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Uint8Array/Uint8Array