ArrayBuffer

O objeto ArrayBuffer é um tipo de dado usado para representar um genérico, buffer de dados binários de tamanho fixo. Você não pode manipular diretamente os conteúdos de um ArrayBuffer;  em vez disso, você cria um objeto ArrayBufferView que representa o buffer em um formato específico, e usa para ler e escrever os conteúdos do buffer.

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

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.prototype
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]) This is an experimental API that should not be used in production code.

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.prototype.

Properties

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Methods

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ArrayBuffer.slice() This API has not been standardized.
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);

Especificações

Especificação Status Comentário
Typed Array Specification Obsoleto Substituído pelo ECMAScript 6
ECMAScript 2015 (6th Edition, ECMA-262)
The definition of 'ArrayBuffer' in that specification.
Padrão Definição inicial no ECMA standard. Specified that new is required.
ECMAScript (ECMA-262)
The definition of 'ArrayBuffer' in that specification.
Padrão em tempo real  

Compatibilidade entre Navegadores

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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 também