Optional options: GridFSBucketOptionsStatic Readonly INDEXWhen the first call to openUploadStream is made, the upload stream will check to see if it needs to create the proper indexes on the chunks and files collections. 当第一次调用openUploadStream时，上传流将检查是否需要在块和文件集合上创建正确的索引。This event is fired either when 1) it determines that no index creation is necessary, 2) when it successfully creates the necessary indexes.当1）确定不需要创建索引时，或当2）成功创建必要的索引时，会触发此事件。
Static Readonly captureStatic captureSets or gets the default captureRejection value for all emitters.设置或获取所有发射器的默认captureRejection值。
Static defaultStatic Readonly errorThis symbol shall be used to install a listener for only monitoring 此符号应用于安装仅用于监视'error' events. 'error'事件的侦听器。Listeners installed using this symbol are called before the regular 在调用常规'error' listeners are called.'error'侦听器之前，将调用使用此符号安装的侦听器。
Installing a listener using this symbol does not change the behavior once an 一旦发出'error' event is emitted, therefore the process will still crash if no regular 'error' listener is installed.'error'事件，使用此符号安装侦听器不会改变行为，因此，如果未安装常规的'error'侦听器，进程仍将崩溃。
Deletes a file with the given id删除具有给定id的文件
The id of the file doc文件文档的id
Rest ...args: Parameters<GridFSBucketEvents[EventKey]>Convenience wrapper around find on the files collection文件集合上的便利包装
Returns a readable stream (GridFSBucketReadStream) for streaming file data from GridFS.为来自GridFS的流式文件数据返回可读流（GridFSBucketReadStream）。
Optional options: GridFSBucketReadStreamOptionsReturns a readable stream (GridFSBucketReadStream) for streaming the file with the given name from GridFS. 返回可读流（GridFSBucketReadStream），用于从GridFS流式传输给定名称的文件。If there are multiple files with the same name, this will stream the most recent file with the given name (as determined by the 如果有多个文件具有相同的名称，这将流式传输具有给定名称的最新文件（由uploadDate field). uploadDate字段确定）。You can set the 您可以设置revision option to change this behavior.revision选项来更改此行为。
Optional options: GridFSBucketReadStreamOptionsWithRevisionReturns a writable stream (GridFSBucketWriteStream) for writing buffers to GridFS. The stream's 'id' property contains the resulting file's id.返回一个可写流（GridFSBucketWriteStream），用于将缓冲区写入GridFS。流的“id”属性包含结果文件的id。
The value of the 'filename' key in the files doc文件文档中“filename”键的值
Optional options: GridFSBucketWriteStreamOptionsOptional settings.可选设置。
Returns a writable stream (GridFSBucketWriteStream) for writing buffers to GridFS for a custom file id. 返回一个可写流（GridFSBucketWriteStream），用于将缓冲区写入自定义文件id的GridFS。The stream's 'id' property contains the resulting file's id.流的“id”属性包含结果文件的id。
Optional options: GridFSBucketWriteStreamOptionsOptional event: string | symbol | EventKeyRenames the file with the given _id to the given string将具有给定_id的文件重命名为给定字符串
the id of the file to rename要重命名的文件的id
new name for the file文件的新名称
Static getReturns a copy of the array of listeners for the event named 返回名为eventName.eventName的事件的侦听器数组的副本。
For 对于EventEmitters this behaves exactly the same as calling .listeners on the emitter.EventEmitter，其行为与在发射器上调用.listeners完全相同。
For 对于EventTargets this is the only way to get the event listeners for the event target. EventTarget，这是获取事件目标的事件侦听器的唯一方法。This is useful for debugging and diagnostic purposes.这对于调试和诊断非常有用。
import { getEventListeners, EventEmitter } from 'node:events';
{
const ee = new EventEmitter();
const listener = () => console.log('Events are fun');
ee.on('foo', listener);
console.log(getEventListeners(ee, 'foo')); // [ [Function: listener] ]
}
{
const et = new EventTarget();
const listener = () => console.log('Events are fun');
et.addEventListener('foo', listener);
console.log(getEventListeners(et, 'foo')); // [ [Function: listener] ]
}
v15.2.0, v14.17.0
Static listenerA class method that returns the number of listeners for the given 一个类方法，用于返回在给定eventNameregistered on the given emitter.emitter上注册的给定eventName的侦听器数。
import { EventEmitter, listenerCount } from 'node:events';
const myEmitter = new EventEmitter();
myEmitter.on('event', () => {});
myEmitter.on('event', () => {});
console.log(listenerCount(myEmitter, 'event'));
// Prints: 2
The emitter to query要查询的发射器
The event name事件名称
v0.9.12
Since v3.2.0 - Use listenerCount instead.
Static onimport { on, EventEmitter } from 'node:events';
import process from 'node:process';
const ee = new EventEmitter();
// Emit later on
process.nextTick(() => {
ee.emit('foo', 'bar');
ee.emit('foo', 42);
});
for await (const event of on(ee, 'foo')) {
// The execution of this inner block is synchronous and it processes one event at a time (even with await). 这个内部块的执行是同步的，它一次处理一个事件（即使有等待）。
// Do not use if concurrent execution is required.如果需要并发执行，请不要使用。
console.log(event); // prints ['bar'] [42]
}
// Unreachable here此处无法访问
Returns an 返回一个迭代AsyncIterator that iterates eventName events. eventName事件的AsyncIterator。It will throw if the 如果EventEmitter emits 'error'. EventEmitter发出'error'，它将抛出。It removes all listeners when exiting the loop. The 它在退出循环时删除所有侦听器。每次迭代返回的value returned by each iteration is an array composed of the emitted event arguments.value是一个由发出的事件参数组成的数组。
An AbortSignal can be used to cancel waiting on events:AbortSignal可用于取消等待事件：
import { on, EventEmitter } from 'node:events';
import process from 'node:process';
const ac = new AbortController();
(async () => {
const ee = new EventEmitter();
// Emit later on
process.nextTick(() => {
ee.emit('foo', 'bar');
ee.emit('foo', 42);
});
for await (const event of on(ee, 'foo', { signal: ac.signal })) {
// The execution of this inner block is synchronous and it processes one event at a time (even with await). 这个内部块的执行是同步的，它一次处理一个事件（即使有等待）。
Do not use if concurrent execution is required.如果需要并发执行，请不要使用。
console.log(event); // prints ['bar'] [42]
}
// Unreachable here
})();
process.nextTick(() => ac.abort());
The name of the event being listened for正在侦听的事件的名称
Optional options: StaticEventEmitterOptionsthat iterates 迭代eventName events emitted by the emitteremitter发出的eventName事件
v13.6.0, v12.16.0
Static onceCreates a 创建一个Promise that is fulfilled when the EventEmitter emits the given event or that is rejected if the EventEmitter emits 'error' while waiting.Promise，该Promise在EventEmitter发出给定事件时实现，或者如果EventEmitter在等待时发出'error'则被拒绝。
The Promise will resolve with an array of all the arguments emitted to the given event.Promise将通过向给定事件发出的所有参数的数组进行解析。
This method is intentionally generic and works with the web platform EventTarget interface, which has no special此方法是有意通用的，可与web平台EventTarget接口配合使用，该接口没有特殊的'error' event semantics and does not listen to the 'error' event.'error'事件语义，也不侦听'error'消息。
import { once, EventEmitter } from 'node:events';
import process from 'node:process';
const ee = new EventEmitter();
process.nextTick(() => {
ee.emit('myevent', 42);
});
const [value] = await once(ee, 'myevent');
console.log(value);
const err = new Error('kaboom');
process.nextTick(() => {
ee.emit('error', err);
});
try {
await once(ee, 'myevent');
} catch (err) {
console.error('error happened', err);
}
The special handling of the 'error' event is only used when events.once()is used to wait for another event. 'error'事件的特殊处理仅在events.once()用于等待另一个事件时使用。If 如果events.once() is used to wait for the 'error' event itself, then it is treated as any other kind of event without special handling:events.once()用于等待'error'事件本身，那么它将被视为任何其他类型的事件，而无需特殊处理：
import { EventEmitter, once } from 'node:events';
const ee = new EventEmitter();
once(ee, 'error')
.then(([err]) => console.log('ok', err.message))
.catch((err) => console.error('error', err.message));
ee.emit('error', new Error('boom'));
// Prints: ok boom
An AbortSignal can be used to cancel waiting for the event:AbortSignal可用于取消等待事件：
import { EventEmitter, once } from 'node:events';
const ee = new EventEmitter();
const ac = new AbortController();
async function foo(emitter, event, signal) {
try {
await once(emitter, event, { signal });
console.log('event emitted!');
} catch (error) {
if (error.name === 'AbortError') {
console.error('Waiting for the event was canceled!');
} else {
console.error('There was an error', error.message);
}
}
}
foo(ee, 'foo', ac.signal);
ac.abort(); // Abort waiting for the event中止等待事件
ee.emit('foo'); // Prints: Waiting for the event was canceled!打印：等待活动已取消！
Optional options: StaticEventEmitterOptionsv11.13.0, v10.16.0
Optional options: StaticEventEmitterOptionsStatic setimport { setMaxListeners, EventEmitter } from 'node:events';
const target = new EventTarget();
const emitter = new EventEmitter();
setMaxListeners(5, target, emitter);
Optional n: numberA non-negative number. The maximum number of listeners per 一个非负数。每个EventTarget event.EventTarget事件的最大侦听器数。
Rest ...eventTargets: (EventEmitter | _DOMEventTarget)[]v15.4.0
Generated using TypeDoc
Constructor for a streaming GridFS interface流式GridFS接口的构造函数