The size
accessor property returns the number of elements in a Set
object.
Description
The value of size
is an integer representing how many entries the Set
object has. A set accessor function for size
is undefined
; you cannot change this property.
Examples
Using size
var mySet = new Set(); mySet.add(1); mySet.add(5); mySet.add("some text") mySet.size; // 3
Specifications
Specification | Status | Comment |
---|---|---|
ECMAScript 2015 (6th Edition, ECMA-262) The definition of 'Set.prototype.size' in that specification. |
Standard | Initial definition. |
ECMAScript 2017 Draft (ECMA-262) The definition of 'Set.prototype.size' in that specification. |
Draft |
Browser compatibility
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
---|---|---|---|---|---|
Basic support | 38 | 19 (19) [1] | 11 | 25 | 7.1 |
Feature | Android | Chrome for Android | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|---|
Basic support | No support | 38 | 19.0 (19) | No support | No support | 8 |
[1] From Gecko 13 (Firefox 13 / Thunderbird 13 / SeaMonkey 2.10) to Gecko 18 (Firefox 18 / Thunderbird 18 / SeaMonkey 2.15 / Firefox OS 1.0.1 / Firefox OS 1.1) the size property was implemented as a Set.prototype.size()
method, this has been changed to a property in later versions conform to the ECMAScript 6 specification (bug 807001).