set.size
set.size
Size
属性将会返回Set
对象中元素的个数。
描述
Size的值表示Set对象拥有多少个元素。通过调用函数的形式访问Size会提示为undefined;并且该值不能够被更改。
示例
使用size
var mySet = new Set(
mySet.add(1
mySet.add(5
mySet.add('some text')
mySet.size; // 3
规范
Specification | Status | Comment |
---|---|---|
ECMAScript 2015 (6th Edition, ECMA-262)The definition of 'Set.prototype.size' in that specification. | Standard | Initial definition. |
ECMAScript Latest Draft (ECMA-262)The definition of 'Set.prototype.size' in that specification. | Draft | |
浏览器兼容性
Feature | Chrome | Edge | Firefox (Gecko) | Internet Explorer | Opera | Safari |
---|---|---|---|---|---|---|
Basic support | 38 | (Yes) | 19 (19) 1 | 11 | 25 | 7.1 |
Feature | Android | Chrome for Android | Edge | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|---|---|
Basic support | No support | 38 | (Yes) | 19.0 (19) | No support | No support | 8 |