Size属性将会返回Set对象中元素的个数。
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描述
size的值是一个整数，表示Set对象有多少条目。size的集合访问函数是undefined; 你不能改变这个属性。
例子
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 |
|---|---|---|
| Standard | 初始定义 | |
| Draft |
浏览器兼容
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
| Feature | Chrome | Edge | Firefox | Internet Explorer | Opera | Safari |
|---|---|---|---|---|---|---|
| Basic support | 38 | 12 | 191 | 11 | 25 | 8 |
| Feature | Android webview | Chrome for Android | Edge mobile | Firefox for Android | Opera Android | iOS Safari | Samsung Internet |
|---|---|---|---|---|---|---|---|
| Basic support | 38 | 38 | 12 | 191 | 25 | 8 | Yes |
1. From Firefox 13 to Firefox 18, 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 2015 specification.