js遍历数组和遍历对象的区别

<script>
    //----------------for用来遍历数组对象--
    var i,myArr = [1,2,3]; for (var i = 0; i < myArr.length; i++) { console.log(i+":"+myArr[i]); }; //---------for-in 用来遍历非数组对象
    var man ={hands:2,legs:2,heads:1}; //为所有的对象添加clone方法，即给内置原型(object,Array,function)增加原型属性,该方法很强大，也很危险
    if(typeof Object.prototype.clone ==="undefined"){ Object.prototype.clone = function(){}; } //     for(var i in man){ if (man.hasOwnProperty(i)) { //filter,只输出man的私有属性
            console.log(i,":",man[i]); }; } //输出结果为print hands:2,legs:2,heads:1

    for(var i in man) {//不使用过滤
        console.log(i,":",man[i]); } //输出结果为
    //hands : 2 index.html:20
    //legs : 2 index.html:20
    //heads : 1 index.html:20
    //clone : function (){} 
    for(var i in man) { if(Object.prototype.hasOwnProperty.call(man,i)) { //过滤
            console.log(i,":",man[i]); } }

 //输出结果为print hands:2,legs:2,heads:1

</script>