JS模式之简单的订阅者和发布者模式完整实例

2019-11-20 12:07:58

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本文实例讲述了JS模式之简单的订阅者和发布者模式。分享给大家供大家参考。具体如下：

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8" /><title>parten</title></head><body><script>var singletonTest = SingletonTest.getInstance({  pointX : 5});console.log(singletonTest.pointX);//easy_Observer_model;function ObserverList(){  this.observerList = [];};ObserverList.prototype.Add = function(obj){  return this.observerList.push(obj);};ObserverList.prototype.Empty = function(){  this.observerList = [];};ObserverList.prototype.Count = function(){  return this.observerList.length;};ObserverList.prototype.Get = function(index){  if(index>-1 && index<this.observerList.length)  return this.observerList[index];};ObserverList.prototype.Insert = function(obj,index){  var pointer = -1;  if(index == 0){    this.observerList.unshift(obj);    pointer = index;  }else if(index == this.observerList.length){    this.observerList.push(obj);    pointer = index;  };  return pointer;};ObserverList.prototype.IndexOf = function(obj,startIndex){  var i = startIndex, pointer = -1;  while(i < this.observerList.length){    if(this.observerList[i] === obj){      pointer = i;    };    i++  };  return pointer;};ObserverList.prototype.RemoveIndexAt = function(index){  if(index === 0){    this.observerList.shift();  }else if(index === this.observerList.length-1){    this.observerList.pop();  };  return index;};function extend(obj,extension){  for(var key in obj){    extension[key] = obj[key];  }};//function Subject(){  this.observers = new ObserverList();};Subject.prototype.AddObserver = function(obj){  this.observers.add(obj)};Subject.prototype.RemoveObserver = function(observer){  this.observers.removeIndexAt( this.observers.IndexOf(observer,0) );};Subject.prototype.Notify = function(context){  var observerCount = this.observers.count();  for(var i=0; i<observerCount; i++){    this.observers.Get(i).update(context);  };}//Pubsub//subscribevar Pubsub = {};(function(q){  var topics = [],    subUid = -1;  q.publish = function(topic,args){    if(!topics[topic]){      return false;    };    var subscribers = topics[topic],      len = subscribers ? subscribers.length : 0;    while(len--){      subscribers[len].func(topic,args);    }    return this;  };  q.subscribe = function(topic,func){    if(!topics[topic]){      topics[topic] = [];    };    var token = (++subUid).toString();    topics[topic].push({      token : token,      func : func    });    return token;  };  q.unsubscribe = function(token){    for(var m in topics){      if(topics[m]){        for(var i=0; i<topics[m].length; i++){          if(topics[m][i].token === token){            topics[m].splice(i,1);            return token;          }        }      };    };    return this;  }})(pubsub);</script></body></html>

希望本文所述对大家的javascript程序设计有所帮助。

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