emitter.prependOnceListener(eventName, listener)

• eventName <string> | <symbol> 事件的名称。

  ¥eventName <string> | <symbol> The name of the event.

• listener <Function> 回调函数

  ¥listener <Function> The callback function

• 返回：<EventEmitter>

  ¥Returns: <EventEmitter>

将名为 eventName 的事件的一次性 listener 函数添加到监听器数组的开头。下次触发 eventName 时，将移除此监听器，然后再调用。

¥Adds a one-time listener 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!');
}); 拷贝

返回对 EventEmitter 的引用，以便可以链式调用。

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