OtherWritableDestinationWritableDestination.onceOn this pageWritableDestination.once() 方法 🌐 WritableDestination.once() method 语法 🌐 Signature interface WritableDestination { once?(event: string, cb: (arg?: unknown) => void): unknown;} 参数 🌐 Parameters 范围 🌐 Parameter 类型 🌐 Type 描述 🌐 Description event string cb (arg?: unknown) => void 返回: unknown