The subarray() method returns a new TypedArray on the same ArrayBuffer store and with the same element types as for this TypedArray object. The begin offset is inclusive and the end offset is exclusive. TypedArray is one of the typed array types.


<var>typedarr</var>ay.subarray([begin [,end]])


begin Optional
Element to begin at. The offset is inclusive. The whole array will be cloned if this value is not specified.
end Optional
Element to end at. The offset is exclusive. If not specified, all elements from the one specified by begin to the end of the array are included in the new view.

Return value

A new TypedArray object.


The range specified by begin and end is clamped to the valid index range for the current array; if the computed length of the new array would be negative, it's clamped to zero. If either begin or end is negative, it refers to an index from the end of the array instead of from the beginning.

Also note that this is creating a new view on the existing buffer; changes to the new object's contents will impact the original object and vice versa.


Using the subarray method

var buffer = new ArrayBuffer(8);
var uint8 = new Uint8Array(buffer);

console.log(uint8); // Uint8Array [ 1, 2, 3, 0, 0, 0, 0, 0 ]

var sub = uint8.subarray(0,4);

console.log(sub);   // Uint8Array [ 1, 2, 3, 0 ]


Specification Status Comment
Typed Array Specification Obsolete Superseded by ECMAScript 6.
ECMAScript 2015 (6th Edition, ECMA-262)
The definition of 'TypedArray.prototype.subarray' in that specification.
Standard Initial definition in an ECMA standard.
ECMAScript 2017 Draft (ECMA-262)
The definition of 'TypedArray.prototype.subarray' in that specification.

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


© 2016 Mozilla Contributors
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.

JavaScript Method Prototype TypedArray TypedArrays