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ArrayBuffer

The ArrayBuffer object is used to represent a generic, fixed-length raw binary data buffer. You can not directly manipulate the contents of an ArrayBuffer; instead, you create one of the typed array objects or a DataView object which represents the buffer in a specific format, and use that to read and write the contents of the 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.

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

ArrayBuffer instances

All ArrayBuffer instances inherit from ArrayBuffer.prototype.

Properties

ArrayBuffer.prototype.constructor
Specifies the function that creates an object's prototype. The initial value is the standard built-in ArrayBuffer constructor.
ArrayBuffer.prototype.byteLength Read only
The size, in bytes, of the array. This is established when the array is constructed and cannot be changed. Read only.

Methods

ArrayBuffer.prototype.slice()
Returns a new ArrayBuffer whose contents are a copy of this ArrayBuffer's bytes from begin, inclusive, up to end, exclusive. If either begin or end is negative, it refers to an index from the end of the array, as opposed to from the beginning.

Example

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);

Specifications

Specification Status Comment
Typed Array Specification Obsolete Superseded by ECMAScript 6.
ECMAScript 2015 (6th Edition, ECMA-262)
The definition of 'ArrayBuffer' in that specification.
Standard Initial definition in an ECMA standard.

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support 7.0 4.0 (2) 10 11.6 5.1
Feature Android Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support 4.0 (Yes) 4.0 (2) 10 11.6 4.2

See also

Document Tags and Contributors

Last updated by: fscholz,