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Class: abstract Listener<E, Options>

The base event class. This class is abstract and is to be extended by subclasses, which should implement the methods. In Sapphire's workflow, listeners are called when the emitter they listen on emits a new message with the same event name.

Examples​

// TypeScript:
import { Events, Listener } from '@sapphire/framework';

// Define a class extending `Listener`, then export it.
// NOTE: You can use `export default` or `export =` too.
export class CoreListener extends Listener<typeof Events.ClientReady> {
  public constructor(context: Listener.LoaderContext) {
    super(context, { event: Events.ClientReady, once: true });
  }

  public run() {
    this.container.client.id ??= this.container.client.user?.id ?? null;
  }
}
// JavaScript:
const { Events, Listener } = require('@sapphire/framework');

// Define a class extending `Listener`, then export it.
module.exports = class CoreListener extends Listener {
  constructor(context) {
    super(context, { event: Events.ClientReady, once: true });
  }

  run() {
    this.container.client.id ??= this.container.client.user?.id ?? null;
  }
}

Extends​

  • Piece<Options, "listeners">

Type Parameters​

Type ParameterDefault type
E extends keyof ClientEvents | symbol""
Options extends OptionsOptions

Constructors​

new Listener()​

new Listener<E, Options>(context: LoaderContext, options: Options): Listener<E, Options>

Parameters​

ParameterType
contextLoaderContext
optionsOptions

Returns​

Listener<E, Options>

Overrides​

`Piece< Options, 'listeners'

.constructor`

Defined in​

projects/framework/src/lib/structures/Listener.ts:70

Properties​

emitter​

readonly emitter: null | EventEmitter<DefaultEventMap>

The emitter, if any.

Since​

2.0.0

Defined in​

projects/framework/src/lib/structures/Listener.ts:54

event​

readonly event: string | symbol

The name of the event the listener listens to.

Since​

2.0.0

Defined in​

projects/framework/src/lib/structures/Listener.ts:60

once​

readonly once: boolean

Whether the listener will be unloaded after the first run.

Since​

2.0.0

Defined in​

projects/framework/src/lib/structures/Listener.ts:66

Methods​

run()​

abstract run(...args: E extends keyof ClientEvents ? ClientEvents[E<E>] : unknown[]): unknown

Parameters​

ParameterType
...argsE extends keyof ClientEvents ? ClientEvents[E<E>] : unknown[]

Returns​

unknown

Defined in​

projects/framework/src/lib/structures/Listener.ts:88

toJSON()​

toJSON(): ListenerJSON

Defines the JSON.stringify behavior of this piece.

Returns​

ListenerJSON

Overrides​

Piece.toJSON

Defined in​

projects/framework/src/lib/structures/Listener.ts:90