JavaScript小数、整数四舍五入方法

<script>

    var sortArr = [

        { name: "Robin Van PurseStrings", age: 30 },

        { name: "Theo Walcott", age: 24 },

        { name: "Bacary Sagna", age: 28  }

    ].sort(function(obj1, obj2) {return obj2.age - obj1.age;});

 

    for(var i=0; i<sortArr.length;i++) {

        alert(sortArr[i].name);

    }

</script>