ArrayBuffer

Experimente

// Create an ArrayBuffer with a size in bytes
const buffer = new ArrayBuffer(8);

console.log(buffer.byteLength);
// Expected output: 8

Syntax

new ArrayBuffer(length)

Parameters

length

The size, in bytes, of the array buffer to create.

Return value

A new ArrayBuffer object of the specified size. Its contents are initialized to 0.

Exceptions

A RangeError is thrown if the length is larger than Number.MAX_SAFE_INTEGER (>= 2 ** 53) or negative.

Description

The ArrayBuffer constructor creates a new ArrayBuffer of the given length in bytes.

Getting an array buffer from existing data

• From a Base64 string
• From a local file

Properties

ArrayBuffer.length

The ArrayBuffer constructor's length property whose value is 1.

get ArrayBuffer[@@species]

The constructor function that is used to create derived objects.

ArrayBuffer

Allows the addition of properties to all ArrayBuffer objects.

Methods

ArrayBuffer.isView(arg)

Returns true if arg is one of the ArrayBuffer views, such as typed array objects or a DataView. Returns false otherwise.

ArrayBuffer.transfer(oldBuffer [, newByteLength])

Returns a new ArrayBuffer whose contents are taken from the oldBuffer's data and then is either truncated or zero-extended by newByteLength.

Instances

All ArrayBuffer instances inherit from ArrayBuffer.

Properties

Methods

ArrayBuffer.slice()

Has the same functionality as ArrayBuffer.prototype.slice().

Exemplo

In this example, we create a 8-byte buffer with a Int32Array view referring to the buffer:

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

Especificaes

Compatibilidade com navegadores

Compatibility notes

Starting with ECMAScript 2015, ArrayBuffer constructors require to be constructed with a new operator. Calling an ArrayBuffer constructor as a function without new, will throw a TypeError from now on.

var dv = ArrayBuffer(10);
// TypedError: calling a builtin ArrayBuffer constructor
// without new is forbidden

var dv = new ArrayBuffer(10);

Veja tambm

• JavaScript typed arrays
• SharedArrayBuffer