obj1 =
{
                "authList": [ ], 
                "enabled": 1, 
                "id": "b3bae8fcde0d4a50b7fbcbbccf4fe216", 
                "lastLogin": 1564363725773, 
                "lastLoginStr": "2019-07-29", 
                "namePinyin": "chenghua", 
                "namePinyinFirst": "c", 
                "rowLocked": 0, 
                "sex": 2, 
                "userAccount": "chenghua", 
                "userName": "lomo"
  }, 


obj2 ={
                "sex": '', 
                "userAccount": "", 
                "userName": ""
}

如上两个对象 如果想让obj2对应的值 等于 obj1里面对应key的值

obj2.sex = obj1.sex
obj2.userName = obj1.userName
...
如果obj2的空属性多的话 这样赋值会很丑陋

有没有更好的赋值的方法