js自定义事件

自定义事件的本质，创建一个对象，然后把事件的名字作为对象的一个属性，然后value是一个[],把此事件的所以回调都push进去。

写一个很基本的，没有把对象暴露出去的js的自定义事件。

 var event = (function(){
   var obj = {};
   var addEvent = function(type,cb){
     if(!obj[type]){
         obj[type] = [];
     }
     return obj[type].push(cb);
   }
   var removeEvent = function(type){
     return obj[type] = null;
   }
   var fireEvent = function(type){
     for(var i = ;i<obj[type].length;i++){
       obj[type][i]();
     }
   }
   return {
     add:addEvent,
     remove:removeEvent,
     fire:fireEvent
   }
 })();
 var on = function(type,param){
   if(typeof param == "function"){
     event.add(type,param);
   }else{
     event.fire(type);
   }
 }
 var off = function(type){
   event().remove(type);
 }
 on("hello",function(){console.log("你好世界");});
 on("hello",function(){console.log("我是飘飘然");});
 on("hello");

这里我们提供一个可以放入sdk中的

  customEvent = (function() {
       var S4, addCustomEvent, cgid, fireCustomEvent, guid, listeners, removeCustomEvent;
       S4 = function() {
         return (((1 + Math.random()) * 0x10000) | 0).toString(16).substring(1);
       };
       guid = function() {
         return S4() + S4() + "-" + S4() + "-" + S4() + "-" + S4() + "-" + S4() + S4() + S4();
       };
       listeners = {};
       cgid = '__ceGUID';//cgid = guid; 目的为了防止框架定义的obj属性和用户定义属性的相同
       addCustomEvent = function(obj, event, callback) {
         obj[cgid] = undefined;
         if (!obj[cgid]) {
           obj[cgid] = "ifvisible.object.event.identifier";
         }
         if (!listeners[obj[cgid]]) {
           listeners[obj[cgid]] = {};
         }
         if (!listeners[obj[cgid]][event]) {
           listeners[obj[cgid]][event] = [];
         }
         return listeners[obj[cgid]][event].push(callback);
       };
       fireCustomEvent = function(obj, event, memo) {
         var ev, j, len, ref, results;
         if (obj[cgid] && listeners[obj[cgid]] && listeners[obj[cgid]][event]) {
           ref = listeners[obj[cgid]][event];
           results = [];
           for (j = 0, len = ref.length; j < len; j++) {
             ev = ref[j];
             results.push(ev(memo || {}));
           }
           return results;
         }
       };
       removeCustomEvent = function(obj, event, callback) {
         var cl, i, j, len, ref;
         if (callback) {
           if (obj[cgid] && listeners[obj[cgid]] && listeners[obj[cgid]][event]) {
             ref = listeners[obj[cgid]][event];
             for (i = j = 0, len = ref.length; j < len; i = ++j) {
               cl = ref[i];
               if (cl === callback) {
                 listeners[obj[cgid]][event].splice(i, 1);
                 return cl;
               }
             }
           }
         } else {
           if (obj[cgid] && listeners[obj[cgid]] && listeners[obj[cgid]][event]) {
             return delete listeners[obj[cgid]][event];
           }
         }
       };
       return {
         add: addCustomEvent,
         remove: removeCustomEvent,
         fire: fireCustomEvent
       };
     })();