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  • 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>
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  • 原文地址:https://www.cnblogs.com/yun007/p/3121393.html
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