Object.keys方法

var data={a:1,b:2,c:9,d:4,e:5};

            console.log(data);//{a: 1, b: 2, c: 9, d: 4, e: 5}

            console.log(Object.keys(data));//["a", "b", "c", "d", "e"]

            Object.keys(data).map((key,item)=>{

                console.log(key,data[key]);//key=>属性名    data[key]=>属性值

            });