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@142vip.nest typeorm.类.ClientSession

mmdapl edited this page Oct 8, 2026 · 1 revision

API 参考 / @142vip/nest-typeorm / ClientSession

类: ClientSession

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:1300

A class representing a client session on the server

NOTE: not meant to be instantiated directly.

theme_extends

构造函数

构造函数

new ClientSession(options?): ClientSession

定义于: node_modules/.pnpm/@types+node@22.10.7/node_modules/@types/node/events.d.ts:134

参数

options?

EventEmitterOptions

返回

ClientSession

继承自

TypedEventEmitter.constructor

属性

clientOptions?

optional clientOptions?: MongoOptions

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:1302


clusterTime?

optional clusterTime?: ClusterTime

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:1306


defaultTransactionOptions

defaultTransactionOptions: TransactionOptions

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:1309


explicit

explicit: boolean

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:1308


hasEnded

hasEnded: boolean

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:1301


operationTime?

optional operationTime?: Timestamp

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:1307


supports

supports: object

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:1303

causalConsistency

causalConsistency: boolean


transaction

transaction: Transaction

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:1310


captureRejections

static captureRejections: boolean

定义于: node_modules/.pnpm/@types+node@22.10.7/node_modules/@types/node/events.d.ts:459

Value: boolean

Change the default captureRejections option on all new EventEmitter objects.

添加于

v13.4.0, v12.16.0

继承自

TypedEventEmitter.captureRejections


captureRejectionSymbol

readonly static captureRejectionSymbol: typeof captureRejectionSymbol

定义于: node_modules/.pnpm/@types+node@22.10.7/node_modules/@types/node/events.d.ts:452

Value: Symbol.for('nodejs.rejection')

See how to write a custom rejection handler.

添加于

v13.4.0, v12.16.0

继承自

TypedEventEmitter.captureRejectionSymbol


defaultMaxListeners

static defaultMaxListeners: number

定义于: node_modules/.pnpm/@types+node@22.10.7/node_modules/@types/node/events.d.ts:498

By default, a maximum of 10 listeners can be registered for any single event. This limit can be changed for individual EventEmitter instances using the emitter.setMaxListeners(n) method. To change the default for allEventEmitter instances, the events.defaultMaxListeners property can be used. If this value is not a positive number, a RangeError is thrown.

Take caution when setting the events.defaultMaxListeners because the change affects all EventEmitter instances, including those created before the change is made. However, calling emitter.setMaxListeners(n) still has precedence over events.defaultMaxListeners.

This is not a hard limit. The EventEmitter instance will allow more listeners to be added but will output a trace warning to stderr indicating that a "possible EventEmitter memory leak" has been detected. For any single EventEmitter, the emitter.getMaxListeners() and emitter.setMaxListeners() methods can be used to temporarily avoid this warning:

import { EventEmitter } from 'node:events'

const emitter = new EventEmitter()
emitter.setMaxListeners(emitter.getMaxListeners() + 1)
emitter.once('event', () => {
  // do stuff
  emitter.setMaxListeners(Math.max(emitter.getMaxListeners() - 1, 0))
})

The --trace-warnings command-line flag can be used to display the stack trace for such warnings.

The emitted warning can be inspected with process.on('warning') and will have the additional emitter, type, and count properties, referring to the event emitter instance, the event's name and the number of attached listeners, respectively. Its name property is set to 'MaxListenersExceededWarning'.

添加于

v0.11.2

继承自

TypedEventEmitter.defaultMaxListeners


errorMonitor

readonly static errorMonitor: typeof errorMonitor

定义于: node_modules/.pnpm/@types+node@22.10.7/node_modules/@types/node/events.d.ts:445

This symbol shall be used to install a listener for only monitoring 'error' events. Listeners installed using this symbol are called before the regular 'error' listeners are called.

Installing a listener using this symbol does not change the behavior once an 'error' event is emitted. Therefore, the process will still crash if no regular 'error' listener is installed.

添加于

v13.6.0, v12.17.0

继承自

TypedEventEmitter.errorMonitor

访问器

id

Getter 签名

get id(): ServerSessionId | undefined

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:1312

The server id associated with this session

返回

ServerSessionId | undefined


isPinned

Getter 签名

get isPinned(): boolean

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:1317

返回

boolean


loadBalanced

Getter 签名

get loadBalanced(): boolean

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:1316

返回

boolean


serverSession

Getter 签名

get serverSession(): ServerSession

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:1313

返回

ServerSession


snapshotEnabled

Getter 签名

get snapshotEnabled(): boolean

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:1315

Whether or not this session is configured for snapshot reads

返回

boolean

方法

[captureRejectionSymbol]()?

optional [captureRejectionSymbol]<K>(error, event, ...args): void

定义于: node_modules/.pnpm/@types+node@22.10.7/node_modules/@types/node/events.d.ts:136

类型参数

K

K

参数

error

Error

event

string | symbol

args

...AnyRest

返回

void

继承自

TypedEventEmitter.[captureRejectionSymbol]


abortTransaction()

abortTransaction(): Promise<Document>

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:1366

Aborts the currently active transaction in this session.

返回

Promise<Document>


addListener()

调用签名

addListener<EventKey>(event, listener): this

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:5079

Alias for emitter.on(eventName, listener).

类型参数
EventKey

EventKey extends "ended"

参数
event

EventKey

listener

ClientSessionEvents[EventKey]

返回

this

添加于

v0.1.26

继承自

TypedEventEmitter.addListener

调用签名

addListener(event, listener): this

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:5080

Alias for emitter.on(eventName, listener).

参数
event

CommonEvents

listener

(eventName, listener) => void

返回

this

添加于

v0.1.26

继承自

TypedEventEmitter.addListener

调用签名

addListener(event, listener): this

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:5081

Alias for emitter.on(eventName, listener).

参数
event

string | symbol

listener

GenericListener

返回

this

添加于

v0.1.26

继承自

TypedEventEmitter.addListener


advanceClusterTime()

advanceClusterTime(clusterTime): void

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:1335

Advances the clusterTime for a ClientSession to the provided clusterTime of another ClientSession

参数

clusterTime

ClusterTime

the $clusterTime returned by the server from another session in the form of a document containing the BSON.Timestamp clusterTime and signature

返回

void


advanceOperationTime()

advanceOperationTime(operationTime): void

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:1329

Advances the operationTime for a ClientSession.

参数

operationTime

Timestamp

the BSON.Timestamp of the operation type it is desired to advance to

返回

void


commitTransaction()

commitTransaction(): Promise<Document>

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:1362

Commits the currently active transaction in this session.

返回

Promise<Document>


emit()

emit<EventKey>(event, ...args): boolean

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:5097

Synchronously calls each of the listeners registered for the event named eventName, in the order they were registered, passing the supplied arguments to each.

Returns true if the event had listeners, false otherwise.

import { EventEmitter } from 'node:events'

const myEmitter = new EventEmitter()

// First listener
myEmitter.on('event', () => {
  console.log('Helloooo! first listener')
})
// Second listener
myEmitter.on('event', (arg1, arg2) => {
  console.log(`event with parameters ${arg1}, ${arg2} in second listener`)
})
// Third listener
myEmitter.on('event', (...args) => {
  const parameters = args.join(', ')
  console.log(`event with parameters ${parameters} in third listener`)
})

console.log(myEmitter.listeners('event'))

myEmitter.emit('event', 1, 2, 3, 4, 5)

// Prints:
// [
//   [Function: firstListener],
//   [Function: secondListener],
//   [Function: thirdListener]
// ]
// Helloooo! first listener
// event with parameters 1, 2 in second listener
// event with parameters 1, 2, 3, 4, 5 in third listener

类型参数

EventKey

EventKey extends "ended"

参数

event

symbol | EventKey

args

...Parameters<ClientSessionEvents[EventKey]>

返回

boolean

添加于

v0.1.26

继承自

TypedEventEmitter.emit


endSession()

endSession(options?): Promise<void>

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:1323

Ends this session on the server

参数

options?

EndSessionOptions

Optional settings. Currently reserved for future use

返回

Promise<void>


equals()

equals(session): boolean

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:1341

Used to determine if this session equals another

参数

session

ClientSession

The session to compare to

返回

boolean


eventNames()

eventNames(): string[]

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:5105

Returns an array listing the events for which the emitter has registered listeners. The values in the array are strings or Symbols.

import { EventEmitter } from 'node:events'

const myEE = new EventEmitter()
myEE.on('foo', () => {})
myEE.on('bar', () => {})

const sym = Symbol('symbol')
myEE.on(sym, () => {})

console.log(myEE.eventNames())
// Prints: [ 'foo', 'bar', Symbol(symbol) ]

返回

string[]

添加于

v6.0.0

继承自

TypedEventEmitter.eventNames


getMaxListeners()

getMaxListeners(): number

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:5106

Returns the current max listener value for the EventEmitter which is either set by emitter.setMaxListeners(n) or defaults to EventEmitter.defaultMaxListeners.

返回

number

添加于

v1.0.0

继承自

TypedEventEmitter.getMaxListeners


incrementTransactionNumber()

incrementTransactionNumber(): void

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:1350

Increment the transaction number on the internal ServerSession

返回

void


inTransaction()

inTransaction(): boolean

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:1352

返回

boolean

whether this session is currently in a transaction or not


listenerCount()

listenerCount<EventKey>(type): number

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:5098

Returns the number of listeners listening for the event named eventName. If listener is provided, it will return how many times the listener is found in the list of the listeners of the event.

类型参数

EventKey

EventKey extends "ended"

参数

type

string | symbol | EventKey

返回

number

添加于

v3.2.0

继承自

TypedEventEmitter.listenerCount


listeners()

listeners<EventKey>(event): ClientSessionEvents[EventKey][]

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:5095

Returns a copy of the array of listeners for the event named eventName.

server.on('connection', (stream) => {
  console.log('someone connected!')
})
console.log(util.inspect(server.listeners('connection')))
// Prints: [ [Function] ]

类型参数

EventKey

EventKey extends "ended"

参数

event

string | symbol | EventKey

返回

ClientSessionEvents[EventKey][]

添加于

v0.1.26

继承自

TypedEventEmitter.listeners


off()

调用签名

off<EventKey>(event, listener): this

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:5091

Alias for emitter.removeListener().

类型参数
EventKey

EventKey extends "ended"

参数
event

EventKey

listener

ClientSessionEvents[EventKey]

返回

this

添加于

v10.0.0

继承自

TypedEventEmitter.off

调用签名

off(event, listener): this

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:5092

Alias for emitter.removeListener().

参数
event

CommonEvents

listener

(eventName, listener) => void

返回

this

添加于

v10.0.0

继承自

TypedEventEmitter.off

调用签名

off(event, listener): this

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:5093

Alias for emitter.removeListener().

参数
event

string | symbol

listener

GenericListener

返回

this

添加于

v10.0.0

继承自

TypedEventEmitter.off


on()

调用签名

on<EventKey>(event, listener): this

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:5082

Adds the listener function to the end of the listeners array for the event named eventName. No checks are made to see if the listener has already been added. Multiple calls passing the same combination of eventName and listener will result in the listener being added, and called, multiple times.

server.on('connection', (stream) => {
  console.log('someone connected!')
})

Returns a reference to the EventEmitter, so that calls can be chained.

By default, event listeners are invoked in the order they are added. The emitter.prependListener() method can be used as an alternative to add the event listener to the beginning of the listeners array.

import { EventEmitter } from 'node:events'

const myEE = new EventEmitter()
myEE.on('foo', () => console.log('a'))
myEE.prependListener('foo', () => console.log('b'))
myEE.emit('foo')
// Prints:
//   b
//   a
类型参数
EventKey

EventKey extends "ended"

参数
event

EventKey

listener

ClientSessionEvents[EventKey]

The callback function

返回

this

添加于

v0.1.101

继承自

TypedEventEmitter.on

调用签名

on(event, listener): this

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:5083

Adds the listener function to the end of the listeners array for the event named eventName. No checks are made to see if the listener has already been added. Multiple calls passing the same combination of eventName and listener will result in the listener being added, and called, multiple times.

server.on('connection', (stream) => {
  console.log('someone connected!')
})

Returns a reference to the EventEmitter, so that calls can be chained.

By default, event listeners are invoked in the order they are added. The emitter.prependListener() method can be used as an alternative to add the event listener to the beginning of the listeners array.

import { EventEmitter } from 'node:events'

const myEE = new EventEmitter()
myEE.on('foo', () => console.log('a'))
myEE.prependListener('foo', () => console.log('b'))
myEE.emit('foo')
// Prints:
//   b
//   a
参数
event

CommonEvents

listener

(eventName, listener) => void

The callback function

返回

this

添加于

v0.1.101

继承自

TypedEventEmitter.on

调用签名

on(event, listener): this

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:5084

Adds the listener function to the end of the listeners array for the event named eventName. No checks are made to see if the listener has already been added. Multiple calls passing the same combination of eventName and listener will result in the listener being added, and called, multiple times.

server.on('connection', (stream) => {
  console.log('someone connected!')
})

Returns a reference to the EventEmitter, so that calls can be chained.

By default, event listeners are invoked in the order they are added. The emitter.prependListener() method can be used as an alternative to add the event listener to the beginning of the listeners array.

import { EventEmitter } from 'node:events'

const myEE = new EventEmitter()
myEE.on('foo', () => console.log('a'))
myEE.prependListener('foo', () => console.log('b'))
myEE.emit('foo')
// Prints:
//   b
//   a
参数
event

string | symbol

listener

GenericListener

The callback function

返回

this

添加于

v0.1.101

继承自

TypedEventEmitter.on


once()

调用签名

once<EventKey>(event, listener): this

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:5085

Adds a one-time listener function for the event named eventName. The next time eventName is triggered, this listener is removed and then invoked.

server.once('connection', (stream) => {
  console.log('Ah, we have our first user!')
})

Returns a reference to the EventEmitter, so that calls can be chained.

By default, event listeners are invoked in the order they are added. The emitter.prependOnceListener() method can be used as an alternative to add the event listener to the beginning of the listeners array.

import { EventEmitter } from 'node:events'

const myEE = new EventEmitter()
myEE.once('foo', () => console.log('a'))
myEE.prependOnceListener('foo', () => console.log('b'))
myEE.emit('foo')
// Prints:
//   b
//   a
类型参数
EventKey

EventKey extends "ended"

参数
event

EventKey

listener

ClientSessionEvents[EventKey]

The callback function

返回

this

添加于

v0.3.0

继承自

TypedEventEmitter.once

调用签名

once(event, listener): this

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:5086

Adds a one-time listener function for the event named eventName. The next time eventName is triggered, this listener is removed and then invoked.

server.once('connection', (stream) => {
  console.log('Ah, we have our first user!')
})

Returns a reference to the EventEmitter, so that calls can be chained.

By default, event listeners are invoked in the order they are added. The emitter.prependOnceListener() method can be used as an alternative to add the event listener to the beginning of the listeners array.

import { EventEmitter } from 'node:events'

const myEE = new EventEmitter()
myEE.once('foo', () => console.log('a'))
myEE.prependOnceListener('foo', () => console.log('b'))
myEE.emit('foo')
// Prints:
//   b
//   a
参数
event

CommonEvents

listener

(eventName, listener) => void

The callback function

返回

this

添加于

v0.3.0

继承自

TypedEventEmitter.once

调用签名

once(event, listener): this

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:5087

Adds a one-time listener function for the event named eventName. The next time eventName is triggered, this listener is removed and then invoked.

server.once('connection', (stream) => {
  console.log('Ah, we have our first user!')
})

Returns a reference to the EventEmitter, so that calls can be chained.

By default, event listeners are invoked in the order they are added. The emitter.prependOnceListener() method can be used as an alternative to add the event listener to the beginning of the listeners array.

import { EventEmitter } from 'node:events'

const myEE = new EventEmitter()
myEE.once('foo', () => console.log('a'))
myEE.prependOnceListener('foo', () => console.log('b'))
myEE.emit('foo')
// Prints:
//   b
//   a
参数
event

string | symbol

listener

GenericListener

The callback function

返回

this

添加于

v0.3.0

继承自

TypedEventEmitter.once


prependListener()

调用签名

prependListener<EventKey>(event, listener): this

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:5099

Adds the listener function to the beginning of the listeners array for the event named eventName. No checks are made to see if the listener has already been added. Multiple calls passing the same combination of eventName and listener will result in the listener being added, and called, multiple times.

server.prependListener('connection', (stream) => {
  console.log('someone connected!')
})

Returns a reference to the EventEmitter, so that calls can be chained.

类型参数
EventKey

EventKey extends "ended"

参数
event

EventKey

listener

ClientSessionEvents[EventKey]

The callback function

返回

this

添加于

v6.0.0

继承自

TypedEventEmitter.prependListener

调用签名

prependListener(event, listener): this

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:5100

Adds the listener function to the beginning of the listeners array for the event named eventName. No checks are made to see if the listener has already been added. Multiple calls passing the same combination of eventName and listener will result in the listener being added, and called, multiple times.

server.prependListener('connection', (stream) => {
  console.log('someone connected!')
})

Returns a reference to the EventEmitter, so that calls can be chained.

参数
event

CommonEvents

listener

(eventName, listener) => void

The callback function

返回

this

添加于

v6.0.0

继承自

TypedEventEmitter.prependListener

调用签名

prependListener(event, listener): this

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:5101

Adds the listener function to the beginning of the listeners array for the event named eventName. No checks are made to see if the listener has already been added. Multiple calls passing the same combination of eventName and listener will result in the listener being added, and called, multiple times.

server.prependListener('connection', (stream) => {
  console.log('someone connected!')
})

Returns a reference to the EventEmitter, so that calls can be chained.

参数
event

string | symbol

listener

GenericListener

The callback function

返回

this

添加于

v6.0.0

继承自

TypedEventEmitter.prependListener


prependOnceListener()

调用签名

prependOnceListener<EventKey>(event, listener): this

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:5102

Adds a one-timelistener function for the event named eventName to the beginning of the listeners array. The next time eventName is triggered, this listener is removed, and then invoked.

server.prependOnceListener('connection', (stream) => {
  console.log('Ah, we have our first user!')
})

Returns a reference to the EventEmitter, so that calls can be chained.

类型参数
EventKey

EventKey extends "ended"

参数
event

EventKey

listener

ClientSessionEvents[EventKey]

The callback function

返回

this

添加于

v6.0.0

继承自

TypedEventEmitter.prependOnceListener

调用签名

prependOnceListener(event, listener): this

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:5103

Adds a one-timelistener function for the event named eventName to the beginning of the listeners array. The next time eventName is triggered, this listener is removed, and then invoked.

server.prependOnceListener('connection', (stream) => {
  console.log('Ah, we have our first user!')
})

Returns a reference to the EventEmitter, so that calls can be chained.

参数
event

CommonEvents

listener

(eventName, listener) => void

The callback function

返回

this

添加于

v6.0.0

继承自

TypedEventEmitter.prependOnceListener

调用签名

prependOnceListener(event, listener): this

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:5104

Adds a one-timelistener function for the event named eventName to the beginning of the listeners array. The next time eventName is triggered, this listener is removed, and then invoked.

server.prependOnceListener('connection', (stream) => {
  console.log('Ah, we have our first user!')
})

Returns a reference to the EventEmitter, so that calls can be chained.

参数
event

string | symbol

listener

GenericListener

The callback function

返回

this

添加于

v6.0.0

继承自

TypedEventEmitter.prependOnceListener


rawListeners()

rawListeners<EventKey>(event): ClientSessionEvents[EventKey][]

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:5096

Returns a copy of the array of listeners for the event named eventName, including any wrappers (such as those created by .once()).

import { EventEmitter } from 'node:events'

const emitter = new EventEmitter()
emitter.once('log', () => console.log('log once'))

// Returns a new Array with a function `onceWrapper` which has a property
// `listener` which contains the original listener bound above
const listeners = emitter.rawListeners('log')
const logFnWrapper = listeners[0]

// Logs "log once" to the console and does not unbind the `once` event
logFnWrapper.listener()

// Logs "log once" to the console and removes the listener
logFnWrapper()

emitter.on('log', () => console.log('log persistently'))
// Will return a new Array with a single function bound by `.on()` above
const newListeners = emitter.rawListeners('log')

// Logs "log persistently" twice
newListeners[0]()
emitter.emit('log')

类型参数

EventKey

EventKey extends "ended"

参数

event

string | symbol | EventKey

返回

ClientSessionEvents[EventKey][]

添加于

v9.4.0

继承自

TypedEventEmitter.rawListeners


removeAllListeners()

removeAllListeners<EventKey>(event?): this

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:5094

Removes all listeners, or those of the specified eventName.

It is bad practice to remove listeners added elsewhere in the code, particularly when the EventEmitter instance was created by some other component or module (e.g. sockets or file streams).

Returns a reference to the EventEmitter, so that calls can be chained.

类型参数

EventKey

EventKey extends "ended"

参数

event?

string | symbol | EventKey

返回

this

添加于

v0.1.26

继承自

TypedEventEmitter.removeAllListeners


removeListener()

调用签名

removeListener<EventKey>(event, listener): this

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:5088

Removes the specified listener from the listener array for the event named eventName.

function callback(stream) {
  console.log('someone connected!')
}
server.on('connection', callback)
// ...
server.removeListener('connection', callback)

removeListener() will remove, at most, one instance of a listener from the listener array. If any single listener has been added multiple times to the listener array for the specified eventName, then removeListener() must be called multiple times to remove each instance.

Once an event is emitted, all listeners attached to it at the time of emitting are called in order. This implies that any removeListener() or removeAllListeners() calls after emitting and before the last listener finishes execution will not remove them fromemit() in progress. Subsequent events behave as expected.

import { EventEmitter } from 'node:events'

class MyEmitter extends EventEmitter {}
const myEmitter = new MyEmitter()

function callbackA() {
  console.log('A')
  myEmitter.removeListener('event', callbackB)
}

function callbackB() {
  console.log('B')
}

myEmitter.on('event', callbackA)

myEmitter.on('event', callbackB)

// callbackA removes listener callbackB but it will still be called.
// Internal listener array at time of emit [callbackA, callbackB]
myEmitter.emit('event')
// Prints:
//   A
//   B

// callbackB is now removed.
// Internal listener array [callbackA]
myEmitter.emit('event')
// Prints:
//   A

Because listeners are managed using an internal array, calling this will change the position indices of any listener registered after the listener being removed. This will not impact the order in which listeners are called, but it means that any copies of the listener array as returned by the emitter.listeners() method will need to be recreated.

When a single function has been added as a handler multiple times for a single event (as in the example below), removeListener() will remove the most recently added instance. In the example the once('ping') listener is removed:

import { EventEmitter } from 'node:events'

const ee = new EventEmitter()

function pong() {
  console.log('pong')
}

ee.on('ping', pong)
ee.once('ping', pong)
ee.removeListener('ping', pong)

ee.emit('ping')
ee.emit('ping')

Returns a reference to the EventEmitter, so that calls can be chained.

类型参数
EventKey

EventKey extends "ended"

参数
event

EventKey

listener

ClientSessionEvents[EventKey]

返回

this

添加于

v0.1.26

继承自

TypedEventEmitter.removeListener

调用签名

removeListener(event, listener): this

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:5089

Removes the specified listener from the listener array for the event named eventName.

function callback(stream) {
  console.log('someone connected!')
}
server.on('connection', callback)
// ...
server.removeListener('connection', callback)

removeListener() will remove, at most, one instance of a listener from the listener array. If any single listener has been added multiple times to the listener array for the specified eventName, then removeListener() must be called multiple times to remove each instance.

Once an event is emitted, all listeners attached to it at the time of emitting are called in order. This implies that any removeListener() or removeAllListeners() calls after emitting and before the last listener finishes execution will not remove them fromemit() in progress. Subsequent events behave as expected.

import { EventEmitter } from 'node:events'

class MyEmitter extends EventEmitter {}
const myEmitter = new MyEmitter()

function callbackA() {
  console.log('A')
  myEmitter.removeListener('event', callbackB)
}

function callbackB() {
  console.log('B')
}

myEmitter.on('event', callbackA)

myEmitter.on('event', callbackB)

// callbackA removes listener callbackB but it will still be called.
// Internal listener array at time of emit [callbackA, callbackB]
myEmitter.emit('event')
// Prints:
//   A
//   B

// callbackB is now removed.
// Internal listener array [callbackA]
myEmitter.emit('event')
// Prints:
//   A

Because listeners are managed using an internal array, calling this will change the position indices of any listener registered after the listener being removed. This will not impact the order in which listeners are called, but it means that any copies of the listener array as returned by the emitter.listeners() method will need to be recreated.

When a single function has been added as a handler multiple times for a single event (as in the example below), removeListener() will remove the most recently added instance. In the example the once('ping') listener is removed:

import { EventEmitter } from 'node:events'

const ee = new EventEmitter()

function pong() {
  console.log('pong')
}

ee.on('ping', pong)
ee.once('ping', pong)
ee.removeListener('ping', pong)

ee.emit('ping')
ee.emit('ping')

Returns a reference to the EventEmitter, so that calls can be chained.

参数
event

CommonEvents

listener

(eventName, listener) => void

返回

this

添加于

v0.1.26

继承自

TypedEventEmitter.removeListener

调用签名

removeListener(event, listener): this

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:5090

Removes the specified listener from the listener array for the event named eventName.

function callback(stream) {
  console.log('someone connected!')
}
server.on('connection', callback)
// ...
server.removeListener('connection', callback)

removeListener() will remove, at most, one instance of a listener from the listener array. If any single listener has been added multiple times to the listener array for the specified eventName, then removeListener() must be called multiple times to remove each instance.

Once an event is emitted, all listeners attached to it at the time of emitting are called in order. This implies that any removeListener() or removeAllListeners() calls after emitting and before the last listener finishes execution will not remove them fromemit() in progress. Subsequent events behave as expected.

import { EventEmitter } from 'node:events'

class MyEmitter extends EventEmitter {}
const myEmitter = new MyEmitter()

function callbackA() {
  console.log('A')
  myEmitter.removeListener('event', callbackB)
}

function callbackB() {
  console.log('B')
}

myEmitter.on('event', callbackA)

myEmitter.on('event', callbackB)

// callbackA removes listener callbackB but it will still be called.
// Internal listener array at time of emit [callbackA, callbackB]
myEmitter.emit('event')
// Prints:
//   A
//   B

// callbackB is now removed.
// Internal listener array [callbackA]
myEmitter.emit('event')
// Prints:
//   A

Because listeners are managed using an internal array, calling this will change the position indices of any listener registered after the listener being removed. This will not impact the order in which listeners are called, but it means that any copies of the listener array as returned by the emitter.listeners() method will need to be recreated.

When a single function has been added as a handler multiple times for a single event (as in the example below), removeListener() will remove the most recently added instance. In the example the once('ping') listener is removed:

import { EventEmitter } from 'node:events'

const ee = new EventEmitter()

function pong() {
  console.log('pong')
}

ee.on('ping', pong)
ee.once('ping', pong)
ee.removeListener('ping', pong)

ee.emit('ping')
ee.emit('ping')

Returns a reference to the EventEmitter, so that calls can be chained.

参数
event

string | symbol

listener

GenericListener

返回

this

添加于

v0.1.26

继承自

TypedEventEmitter.removeListener


setMaxListeners()

setMaxListeners(n): this

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:5107

By default EventEmitters will print a warning if more than 10 listeners are added for a particular event. This is a useful default that helps finding memory leaks. The emitter.setMaxListeners() method allows the limit to be modified for this specific EventEmitter instance. The value can be set to Infinity (or 0) to indicate an unlimited number of listeners.

Returns a reference to the EventEmitter, so that calls can be chained.

参数

n

number

返回

this

添加于

v0.3.5

继承自

TypedEventEmitter.setMaxListeners


startTransaction()

startTransaction(options?): void

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:1358

Starts a new transaction with the given options.

参数

options?

TransactionOptions

Options for the transaction

返回

void


toBSON()

toBSON(): never

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:1370

This is here to ensure that ClientSession is never serialized to BSON.

返回

never


withTransaction()

withTransaction<T>(fn, options?): Promise<Document | undefined>

定义于: node_modules/.pnpm/typeorm@0.3.30_ioredis@5.6.0_mongodb@6.19.0_mssql@11.0.1_mysql2@3.15.1_pg@8.11.3_ts-node@10.9_6zvdq3z7xgsf663jy3j6oymho4/node_modules/typeorm/driver/mongodb/typings.d.ts:1392

Runs a provided callback within a transaction, retrying either the commitTransaction operation or entire transaction as needed (and when the error permits) to better ensure that the transaction can complete successfully.

IMPORTANT: This method requires the user to return a Promise, and await all operations. Any callbacks that do not return a Promise will result in undefined behavior.

类型参数

T

T = void

参数

fn

WithTransactionCallback<T>

callback to run within a transaction

options?

TransactionOptions

optional settings for the transaction

返回

Promise<Document | undefined>

A raw command response or undefined

备注

This function:

  • Will return the command response from the final commitTransaction if every operation is successful (can be used as a truthy object)
  • Will return undefined if the transaction is explicitly aborted with await session.abortTransaction()
  • Will throw if one of the operations throws or throw statement is used inside the withTransaction callback

Checkout a descriptive example here:

参阅

https://www.mongodb.com/developer/quickstart/node-transactions/


addAbortListener()

static addAbortListener(signal, resource): Disposable

定义于: node_modules/.pnpm/@types+node@22.10.7/node_modules/@types/node/events.d.ts:437

Experimental

Listens once to the abort event on the provided signal.

Listening to the abort event on abort signals is unsafe and may lead to resource leaks since another third party with the signal can call e.stopImmediatePropagation(). Unfortunately Node.js cannot change this since it would violate the web standard. Additionally, the original API makes it easy to forget to remove listeners.

This API allows safely using AbortSignals in Node.js APIs by solving these two issues by listening to the event such that stopImmediatePropagation does not prevent the listener from running.

Returns a disposable so that it may be unsubscribed from more easily.

import { addAbortListener } from 'node:events'

function example(signal) {
  let disposable
  try {
    signal.addEventListener('abort', e => e.stopImmediatePropagation())
    disposable = addAbortListener(signal, (e) => {
      // Do something when signal is aborted.
    })
  }
  finally {
    disposable?.[Symbol.dispose]()
  }
}

参数

signal

AbortSignal

resource

(event) => void

返回

Disposable

Disposable that removes the abort listener.

添加于

v20.5.0

继承自

TypedEventEmitter.addAbortListener


getEventListeners()

static getEventListeners(emitter, name): Function[]

定义于: node_modules/.pnpm/@types+node@22.10.7/node_modules/@types/node/events.d.ts:358

Returns a copy of the array of listeners for the event named eventName.

For EventEmitters this behaves exactly the same as calling .listeners on the emitter.

For EventTargets this is the only way to get the event listeners for the event target. This is useful for debugging and diagnostic purposes.

import { EventEmitter, getEventListeners } 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] ]
}

参数

emitter

EventEmitter<DefaultEventMap> | EventTarget

name

string | symbol

返回

Function[]

添加于

v15.2.0, v14.17.0

继承自

TypedEventEmitter.getEventListeners


getMaxListeners()

static getMaxListeners(emitter): number

定义于: node_modules/.pnpm/@types+node@22.10.7/node_modules/@types/node/events.d.ts:387

Returns the currently set max amount of listeners.

For EventEmitters this behaves exactly the same as calling .getMaxListeners on the emitter.

For EventTargets this is the only way to get the max event listeners for the event target. If the number of event handlers on a single EventTarget exceeds the max set, the EventTarget will print a warning.

import { EventEmitter, getMaxListeners, setMaxListeners } from 'node:events'

{
  const ee = new EventEmitter()
  console.log(getMaxListeners(ee)) // 10
  setMaxListeners(11, ee)
  console.log(getMaxListeners(ee)) // 11
}
{
  const et = new EventTarget()
  console.log(getMaxListeners(et)) // 10
  setMaxListeners(11, et)
  console.log(getMaxListeners(et)) // 11
}

参数

emitter

EventEmitter<DefaultEventMap> | EventTarget

返回

number

添加于

v19.9.0

继承自

TypedEventEmitter.getMaxListeners


listenerCount()

static listenerCount(emitter, eventName): number

定义于: node_modules/.pnpm/@types+node@22.10.7/node_modules/@types/node/events.d.ts:330

A class method that returns the number of listeners for the given eventName registered on the given emitter.

import { EventEmitter, listenerCount } from 'node:events'

const myEmitter = new EventEmitter()
myEmitter.on('event', () => {})
myEmitter.on('event', () => {})
console.log(listenerCount(myEmitter, 'event'))
// Prints: 2

参数

emitter

EventEmitter

The emitter to query

eventName

string | symbol

The event name

返回

number

添加于

v0.9.12

已被弃用

Since v3.2.0 - Use listenerCount instead.

继承自

TypedEventEmitter.listenerCount


on()

调用签名

static on(emitter, eventName, options?): AsyncIterator<any[]>

定义于: node_modules/.pnpm/@types+node@22.10.7/node_modules/@types/node/events.d.ts:303

import { EventEmitter, on } 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). Do not use
  // if concurrent execution is required.
  console.log(event) // prints ['bar'] [42]
}
// Unreachable here

Returns an AsyncIterator that iterates eventName events. It will throw if the EventEmitter emits 'error'. It removes all listeners when exiting the loop. The value returned by each iteration is an array composed of the emitted event arguments.

An AbortSignal can be used to cancel waiting on events:

import { EventEmitter, on } 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). Do not use
    // if concurrent execution is required.
    console.log(event) // prints ['bar'] [42]
  }
  // Unreachable here
})()

process.nextTick(() => ac.abort())

Use the close option to specify an array of event names that will end the iteration:

import { EventEmitter, on } 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)
  ee.emit('close')
})

for await (const event of on(ee, 'foo', { close: ['close'] })) {
  console.log(event) // prints ['bar'] [42]
}
// the loop will exit after 'close' is emitted
console.log('done') // prints 'done'
参数
emitter

EventEmitter

eventName

string | symbol

options?

StaticEventEmitterIteratorOptions

返回

AsyncIterator<any[]>

An AsyncIterator that iterates eventName events emitted by the emitter

添加于

v13.6.0, v12.16.0

继承自

TypedEventEmitter.on

调用签名

static on(emitter, eventName, options?): AsyncIterator<any[]>

定义于: node_modules/.pnpm/@types+node@22.10.7/node_modules/@types/node/events.d.ts:308

import { EventEmitter, on } 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). Do not use
  // if concurrent execution is required.
  console.log(event) // prints ['bar'] [42]
}
// Unreachable here

Returns an AsyncIterator that iterates eventName events. It will throw if the EventEmitter emits 'error'. It removes all listeners when exiting the loop. The value returned by each iteration is an array composed of the emitted event arguments.

An AbortSignal can be used to cancel waiting on events:

import { EventEmitter, on } 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). Do not use
    // if concurrent execution is required.
    console.log(event) // prints ['bar'] [42]
  }
  // Unreachable here
})()

process.nextTick(() => ac.abort())

Use the close option to specify an array of event names that will end the iteration:

import { EventEmitter, on } 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)
  ee.emit('close')
})

for await (const event of on(ee, 'foo', { close: ['close'] })) {
  console.log(event) // prints ['bar'] [42]
}
// the loop will exit after 'close' is emitted
console.log('done') // prints 'done'
参数
emitter

EventTarget

eventName

string

options?

StaticEventEmitterIteratorOptions

返回

AsyncIterator<any[]>

An AsyncIterator that iterates eventName events emitted by the emitter

添加于

v13.6.0, v12.16.0

继承自

TypedEventEmitter.on


once()

调用签名

static once(emitter, eventName, options?): Promise<any[]>

定义于: node_modules/.pnpm/@types+node@22.10.7/node_modules/@types/node/events.d.ts:217

Creates a Promise that is fulfilled when the EventEmitter emits the given event or that is rejected if the EventEmitter emits 'error' while waiting. The Promise will resolve with an array of all the arguments emitted to the given event.

This method is intentionally generic and works with the web platform EventTarget interface, which has no special'error' event semantics and does not listen to the 'error' event.

import { EventEmitter, once } 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. If events.once() is used to wait for the 'error' event itself, then it is treated as any other kind of event without special handling:

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:

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
ee.emit('foo') // Prints: Waiting for the event was canceled!
参数
emitter

EventEmitter

eventName

string | symbol

options?

StaticEventEmitterOptions

返回

Promise<any[]>

添加于

v11.13.0, v10.16.0

继承自

TypedEventEmitter.once

调用签名

static once(emitter, eventName, options?): Promise<any[]>

定义于: node_modules/.pnpm/@types+node@22.10.7/node_modules/@types/node/events.d.ts:222

Creates a Promise that is fulfilled when the EventEmitter emits the given event or that is rejected if the EventEmitter emits 'error' while waiting. The Promise will resolve with an array of all the arguments emitted to the given event.

This method is intentionally generic and works with the web platform EventTarget interface, which has no special'error' event semantics and does not listen to the 'error' event.

import { EventEmitter, once } 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. If events.once() is used to wait for the 'error' event itself, then it is treated as any other kind of event without special handling:

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:

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
ee.emit('foo') // Prints: Waiting for the event was canceled!
参数
emitter

EventTarget

eventName

string

options?

StaticEventEmitterOptions

返回

Promise<any[]>

添加于

v11.13.0, v10.16.0

继承自

TypedEventEmitter.once


setMaxListeners()

static setMaxListeners(n?, ...eventTargets): void

定义于: node_modules/.pnpm/@types+node@22.10.7/node_modules/@types/node/events.d.ts:402

import { EventEmitter, setMaxListeners } from 'node:events'

const target = new EventTarget()
const emitter = new EventEmitter()

setMaxListeners(5, target, emitter)

参数

n?

number

A non-negative number. The maximum number of listeners per EventTarget event.

eventTargets

...(EventEmitter<DefaultEventMap> | EventTarget)[]

Zero or more {EventTarget} or {EventEmitter} instances. If none are specified, n is set as the default max for all newly created {EventTarget} and {EventEmitter} objects.

返回

void

添加于

v15.4.0

继承自

TypedEventEmitter.setMaxListeners

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