观察者实例 

<!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>无标题文档</title>
</head>

<body>
<script type="text/javascript">
var ObserverObj = {  /*依赖对象*/
    FirstName: "J",
    LastName: "Q",
    Id: 1
}

var ObserverManager = { /*观察器*/
    Observers:[], /*观察对象集*/
    AddObserver: function(item){/*加入观察对象*/
        this.Observers.push(item);
    },
    Change: function(obj){  /*改变对象行为*/
        for(var item in obj){
            ObserverObj[item] = obj[item];
        }//改变数据依赖对象数据
        for(var i = 0,len = this.Observers.length; i < len; i++){
            var item = this.Observers[i];
            item.Display();        //对象改变后，改变观察对象的行为Display; 为统一的接口
        }
    }
}

var Header = function(){    /*观察对象Header*/
    this.Display = function(){
        alert(ObserverObj.FirstName);
    }
}

var Content = function(){    /*观察对象Content*/
    this.Display = function(){
        alert(ObserverObj.LastName);
    }
}

var Foot = function(){    /*观察对象Foot*/
    this.Display = function(){
        alert(ObserverObj.Id);
    }
}

/*绑定观察器动作*/
ObserverManager.AddObserver(new Header());
ObserverManager.AddObserver(new Content());
ObserverManager.AddObserver(new Foot());
</script>
<!--使用方法-->
<a href="javascript://" onclick="ObserverManager.Change({FirstName:'江'});">改变FirstName</a>
<a href="javascript://" onclick="ObserverManager.Change({LastName:'琪'});">改变LastName</a>
<a href="javascript://" onclick="ObserverManager.Change({Id:2});">改变Id</a>

</body>
</html>

 

posted @ 2014-08-04 16:15  JQ(奇想)  阅读(280)  评论(0)  编辑  收藏  举报