迭代对象及其子对象的属性[重复]

Question

如何迭代对象及其子对象的属性？我在中使用了，但无法获取歌曲信息：/

let discos = [];

let disco1 = {
    discoName: 'name disco1',
    band: 'band name',
    code: 1,
    songs: [
        { 'songName': 'Song Name',
          'duration': 200,
       },
    ],
};
let disco2 = {
    discoName: 'name disco 2',
    band: 'band name 2',
    code: 1,
    songs: [
        { 'songName': 'Song Name 0',
          'duration': 200,
       },
    ],
};

discos.push(disco1,disco2);

for (let disco in discos){
    console.log(discos[disco].discoName);
}

Answer 1

如果您想要一个真正的递归解决方案，您将需要使用递归，因为这不能使用for。。在中：

let discos = [];

let disco1 = {
    discoName: 'name disco1',
    band: 'band name',
    code: 1,
    songs: [
        { 'songName': 'Song Name',
          'duration': 200,
       },
    ],
};
let disco2 = {
    discoName: 'name disco 2',
    band: 'band name 2',
    code: 1,
    songs: [
        { 'songName': 'Song Name 0',
          'duration': 200,
       },
    ],
};

discos.push(disco1,disco2);

const visitRec = (obj, visitor) => {
  if (obj instanceof Array) {
    obj.forEach(e => visitRec(e, visitor));
  } else if (typeof obj == 'object') {
    for (let key in obj) {
      visitRec(obj[key], visitor);
    }
  } else {
    visitor(obj);
  }
}

visitRec(discos, console.log);