javascript - 在数组上创建多个对象循环

Question

所以我有一个数组，它在对象的数组中存储每个用户的爱好。

var hobbies = [
  {
    "id": 1,
    "hobbies": []
  },

  {
    "id": 2,
    "hobbies": [
      "football"
    ]
  },
  {
    "id": 3,
    "hobbies": [
      "football",
      "basketball"
    ]
  }
]

我想返回的是一个新的对象数组，但每个爱好都分成了自己的对象，如下所示。

var result = [
  {
    "id": 2,
    "hobby": "football"
  },
 {
    "id": 3,
    "hobby": "football"
  },
 {
    "id": 3,
    "hobby": "basketball"
  }
]

目前的情况是

hobbies.filter((f, i) => f.hobbies.length > 0).map((p, i) => {
    while (i < p.hobbies.length) {
 return { id : p.id, hobby : p.hobbies[i] };
}
  });

只返回

[
  {
    "id": 2,
    "hobby": "football"
  },
  {
    "id": 3,
    "hobby": "basketball"
  }
]

Answer 1

您可以将 array#reduce 与 array#map 一起使用。遍历每个对象，然后遍历 hobbies 的每个 hobby 并创建对象。

var hobbies = [ { "id": 1, "hobbies": [] }, { "id": 2, "hobbies": [ "football" ] }, { "id": 3, "hobbies": [ "football", "basketball" ] } ],
    result = hobbies.reduce((r, {id, hobbies}) => r.concat(hobbies.map(hobby => ({id, hobby}))), []);
console.log(result);