求助，给object的key值加一个前缀，如何用js或jq实现

Question

var obj = {"a":1,"b":2}
var obj2 = {"qqq.a":1,"qqq.b":2}
想通过js方法，让obj的每个key值加一个前缀qqq，变成obj2？
求教各位大虾指点下

Answer 1

var obj = {"a":1,"b":2};
var obj2 = {};
Object.keys(obj).forEach(key => obj2['qqq.'+key] = obj[key]);
console.log(obj2)