Nodejs删除事件监听器

希望得到一些帮助。 我是Nodejs新手，想知道是否有可能删除这个自定义事件发射器。 这些代码大部分来自Pedro Teixeira的Hand on nodejs。 我在底部的function是试图删除您在本书中设置的自定义事件发射器。

var util = require('util'); var EventEmitter = require('events').EventEmitter; // Pseudo-class named ticker that will self emit every 1 second. var Ticker = function() { var self = this; setInterval(function() { self.emit('tick'); }, 1000); }; // Bind the new EventEmitter to the sudo class. util.inherits(Ticker, EventEmitter); // call and instance of the ticker class to get the first // event started. Then let the event emitter run the infinante loop. var ticker = new Ticker(); ticker.on('tick', function() { console.log('Tick'); }); (function tock() { setInterval(function() { console.log('Tock'); EventEmitter.removeListener('Ticker',function() { console.log("Clocks Dead!"); }); }, 5000); })(); 

Answer 1

您需要使用ticker对象的removeListener方法，而不是EventEmitter。 第一个参数是事件名称，第二个链接到要删除的事件侦听器。

这个代码应该工作：

 var util = require('util'); var EventEmitter = require('events').EventEmitter; // Pseudo-class named ticker that will self emit every 1 second. var Ticker = function() { var self = this; setInterval(function() { self.emit('tick'); }, 1000); }; // Bind the new EventEmitter to the sudo class. util.inherits(Ticker, EventEmitter); // call and instance of the ticker class to get the first // event started. Then let the event emitter run the infinante loop. var ticker = new Ticker(); var tickListener = function() { console.log('Tick'); }; ticker.on('tick', tickListener); (function tock() { setTimeout(function() { console.log('Tock'); ticker.removeListener('tick', tickListener); console.log("Clocks Dead!"); }, 5000); })(); 

Answer 2

https://nodejs.org/api/events.html#events_emitter_removelistener_eventname_listener如果你检查上面的链接使用是EventEmitter.removeListener("eventName",listenerFunc)所以让我们假设我有以下情况

 const {EventEmitter} =require("events") //lets construct our emitter object const myEmitter=new EventEmitter() //and our listener which has to be a named func if we want to identify it later for removing function myListenerFunc(d){ console.log(d) } //adding the emitter myEmitter.on("data",myListenerFunc) //lets remove it after a while //... some time passed something was done //... some more time passes something else was done //we dont need the listener anymore lets remove it myEmitter.removeListener("data",myListenerFunc) //alternatively if you want to remove all listeners myEmitter.removeAllListeners(["data"/* if you need list all the event names in this array*/])