Function on

src/dd-base-impl.ts:37–39

* Register an event callback for the specified event. * * @param event - Event name to listen for * @param callback - Function to call when event occurs

(event: string, callback: EventCallback)

   * @param callback - Function to call when event occurs
   */
  public on(event: string, callback: EventCallback): void {
    this._eventRegister[event] = callback;
  }

  /**
   * Unregister an event callback for the specified event.