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Complete Example of Simple Subscriber and Publisher Pattern in JS Pattern_Javascript Skills

WBOY
WBOYOriginal
2016-05-16 15:52:191327browse

The examples in this article describe the simple subscriber and publisher patterns of JS pattern. Share it with everyone for your reference. The details are as follows:

<!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//subscribe
var Pubsub = {};
(function(q){
  var topics = [],
    subUid = -1;
  q.publish = function(topic,args){
    if(!topics[topic]){
      return false;
    };
    var subscribers = topics[topic],
      len = subscribers &#63; 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>

I hope this article will be helpful to everyone’s JavaScript programming design.

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