Set.prototype[Symbol.iterator]()
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 [Symbol.iterator]() 方法实现了 可迭代协议 并允许大多数需要迭代的语法使用 Set 对象，例如 扩展语法 和 for...of 循环。它返回一个 设置迭代器对象，该 设置迭代器对象 产生按插入顺序排列的集合的值。
¥The [Symbol.iterator]() method of Set instances implements the iterable protocol and allows Set objects to be consumed by most syntaxes expecting iterables, such as the spread syntax and for...of loops. It returns a set iterator object that yields the values of the set in insertion order.
该属性的初始值与 Set.prototype.values 属性的初始值是相同的函数对象。
¥The initial value of this property is the same function object as the initial value of the Set.prototype.values property.
Try it
语法
参数
返回值
¥Return value
与 Set.prototype.values() 返回值相同：一个新的 可迭代的迭代器对象，它产生该集合的值。
¥The same return value as Set.prototype.values(): a new iterable iterator object that yields the values of the set.
示例
使用 for...of 循环进行迭代
¥Iteration using for...of loop
请注意，你很少需要直接调用此方法。[Symbol.iterator]() 方法的存在使得 Set 对象成为 iterable，像 for...of 循环这样的迭代语法会自动调用该方法来获取要循环的迭代器。
¥Note that you seldom need to call this method directly. The existence of the [Symbol.iterator]() method makes Set objects iterable, and iterating syntaxes like the for...of loop automatically call this method to obtain the iterator to loop over.
const mySet = new Set();
mySet.add("0");
mySet.add(1);
mySet.add({});
for (const v of mySet) {
console.log(v);
}
手动滚动迭代器
¥Manually hand-rolling the iterator
你仍然可以手动调用返回的迭代器对象的 next() 方法，以实现对迭代过程的最大控制。
¥You may still manually call the next() method of the returned iterator object to achieve maximum control over the iteration process.
const mySet = new Set();
mySet.add("0");
mySet.add(1);
mySet.add({});
const setIter = mySet[Symbol.iterator]();
console.log(setIter.next().value); // "0"
console.log(setIter.next().value); // 1
console.log(setIter.next().value); // {}
规范
| Specification |
|---|
| ECMAScript Language Specification # sec-set.prototype-@@iterator |
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