js 面向对象

一、js对象的基本操作

window.onload=function(){
        //创建对象
        //var obj = new Object();
        var obj={};
        //设置属性
        obj.name="张安";
        obj.age=20;
        obj["sex"]="男";
        obj.say=function(){
            alert(this.name);
        }
        //访问对象的属性
        console.info(obj.name);
        obj.say();
        // delete 删除 对象的属性或方法
        delete obj.age;
        // for in 遍历一个js对象
        for(var attribute in obj){
           console.info(attribute+"<=======>"+obj[attribute]);
        }
        
    }

  使用js模拟java中的map

window.onload=function(){
        var map=new Map();
        map.put("A","a");
        map.put("B","b");
        map.put("C","c");
        map.put("D",0);
        var size=map.size();// 4
        var value=map.get("D");//d
        map.eachMap(function(key,value){
            alert(key+"______"+value);
        });

    }
    function Map(){
        var obj={};
        this.put=function(key,value){
            obj[key]=value;
        };
        this.size=function(){
            var count=0;
            for(var attr in obj){
                count++;
            }
            return count;
        };
        this.get=function(key){
            if(obj[key]|| obj[key]===0 ||obj[key]===false){
                return obj[key];
            }else{
                return null;
            }
        };
        this.remove=function(){
            if(obj[key]|| obj[key]===0 ||obj[key]===false){
                delete obj[key];
            }
        };
        this.eachMap=function(fn){
            for(var attr in obj){
                fn(attr,obj[attr]);
            }
        }
    }