jsの配列とオブジェクトを比較し、オブジェクトにこの値があればそれを取り出します。

取得されたオブジェクト:

js

封装比对
const capitals = {
   "usa": "Washington DC",
   "uk": "London",
   "india": "New Delhi",
   "italy": "rome",
   "japan": "tokyo",
   "germany": "berlin",
   "china": "shanghai",
   "spain": "madrid",
   "france": "paris",
   "portugal": "lisbon"
};
const countries = ["uk", "india", "germany", "china", "france"];
const filterObject = (obj, arr) => {
   const newObj = {};
   for(key in obj){
      if(arr.includes(key)){
         newObj[key] = obj[key];
      };
   };
   return newObj;
};
console.log(filterObject(capitals, countries));