Set.prototype.add()

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.

Set 实例的 add() 方法会在该集合中插入一个具有指定值的新元素,如果该 Set 对象中没有具有相同值的元素。

尝试一下

const set1 = new Set();

set1.add(42);
set1.add(42);
set1.add(13);

for (const item of set1) {
  console.log(item);
  // Expected output: 42
  // Expected output: 13
}

语法

js
add(value)

参数

value

要添加到 Set 对象的元素的值。

返回值

添加了值的 Set 对象。

示例

使用 add() 方法

js
const mySet = new Set();

mySet.add(1);
mySet.add(5).add("some text"); // 可以链式调用

console.log(mySet);
// Set [1, 5, "some text"]

规范

Specification
ECMAScript® 2025 Language Specification
# sec-set.prototype.add

浏览器兼容性

Report problems with this compatibility data on GitHub
desktopmobileserver
Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
Deno
Node.js
add

Legend

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Full support
Full support

参见