AsyncIterator.prototype[@@asyncIterator]()

AsyncIterator 实例的 [@@asyncIterator]() 方法实现了 异步可迭代协议，并允许大多数需要异步迭代的语法（例如 for await...of 循环）使用内置异步迭代器。它返回 this 的值，这是异步迭代器对象本身。

¥The [@@asyncIterator]() method of AsyncIterator instances implements the async iterable protocol and allows built-in async iterators to be consumed by most syntaxes expecting async iterables, such as for await...of loops. It returns the value of this, which is the async iterator object itself.

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语法

¥Syntax

js
asyncIterator[Symbol.asyncIterator]()

参数

¥Parameters

没有任何。

¥None.

返回值

¥Return value

this 的值，它是异步迭代器对象本身。

¥The value of this, which is the async iterator object itself.

示例

¥Examples

使用 for wait...of 循环进行迭代

¥Iteration using for await...of loop

请注意，你很少需要直接调用此方法。@@asyncIterator 方法的存在使得所有内置的异步迭代器都变成了 异步可迭代，像 for await...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异步迭代器。

¥Note that you seldom need to call this method directly. The existence of the @@asyncIterator method makes all built-in async iterators async iterable, and iterating syntaxes like the for await...of loop automatically calls this method to obtain the async iterator to loop over.

js
const asyncIterator = (async function* () {
  yield 1;
  yield 2;
  yield 3;
})();
(async () => {
  for await (const value of asyncIterator) {
    console.log(value);
  }
})();
// Logs: 1, 2, 3

规范

Specification
ECMAScript Language Specification
# sec-asynciteratorprototype-asynciterator

¥Specifications

浏览器兼容性

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¥Browser compatibility

也可以看看

¥See also