<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta content="width=device-width, initial-scale=1.0"> <meta http-equiv="X-UA-Compatible" content="ie=edge"> <title>Document</title> </head> <body> <script> var pubsub = (function(){ var q = {} topics = {}, subUid = -1; //发布消息 q.publish = function(topic, args) { //判断有没有当前的话题 if(!topics[topic]) {return;} var subs = topics[topic],//当前话题订阅者数组 len = subs.length; while(len--) { subs[len].func(topic, args); } return this; }; //订阅事件 //接收两个参数 要订阅的话题，处理程序 q.subscribe = function(topic, func) { //如果当前话题已经有订阅者，获取到订阅者数组 //一个话题名下的 订阅者事件可以是多个fn1, fn2, fn3 topics[topic] = topics[topic] ? topics[topic] : []; //给每个订阅者添加唯一的token var token = (++subUid).toString(); topics[topic].push({ token : token, func : func }); return token; }; //取消订阅 q.unsubscribe = function(token){ Object.keys(topics).map( key => { topics[key].map((fn, fnIndex) => { if(fn.token == token){ topics[key].splice(fnIndex,1) } }) }) } return q; })(); //触发的事件(订阅者的处理程序) var logmsg1 = function(topics, data) { console.log("logging1:" + topics + ":" + data); } var logmsg2 = function(topic, data) { console.log("logging2:" + topic + ":" + data,'我是订阅者2'); } //监听指定的消息'msgName' var sub1 = pubsub.subscribe('msgName', logmsg1); var sub2 = pubsub.subscribe('msgName', logmsg2); //pubsub.unsubscribe(sub1) //发布消息'msgName' pubsub.publish('msgName', 'hello world'); //发布无人监听的消息'msgName1' pubsub.publish('anotherMsgName', 'me too!'); </script> </body> </html>
运行结果：
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更多关于JavaScript相关内容感兴趣的读者可查看本站专题：《javascript面向对象入门教程》、《JavaScript错误与调试技巧总结》、《JavaScript数据结构与算法技巧总结》、《JavaScript遍历算法与技巧总结》及《JavaScript数学运算用法总结》