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var family = {
  name: '小明家',
  members: {
    father: '老爸',
    mom: '老媽',
    ming: '小明',

var newFamily = {};
for (var key in family) {
  // console.log(key);
  newFamily[key] = family[key];
// 物件內第一層成功拷貝,family與newFamily各自獨立 = '大明家';
console.log(family, newFamily);

// 物件內第二層還是有傳參考特性,所以會一併修改到 family.members.ming 
newFamily.members.ming = '大明';
console.log(family === newFamily);