on - Cognigy Documentation

Adds an event listener for a specific event. See the Event Reference for all available events.

Signature

client.on<T extends EventName>(event: T, callback: EventCallback<T>): this;

Parameters

Parameter	Type	Description	Required
`event`	`EventName`	The name of the event to listen for.	Yes
`callback`	`EventCallback<T>`	The callback function to invoke when the event is emitted.	Yes

Returns

this — the client instance, allowing method chaining.

Example

client.on('answered', (session) => {
  console.log('Call answered:', session.id);
});

client.on('error', (error) => {
  console.error('SDK error:', error.message);
});

Type-Safe Event Handling

import type { WebRTCClientEvents } from '@cognigy/click-to-call-sdk';

const handleAnswered: WebRTCClientEvents['answered'] = (session) => {
  console.log('Call answered:', session.id);
};

client.on('answered', handleAnswered);

More Information

Last modified on November 3, 2026