javascript - 通过在 JSON 数据中查找值来创建新的对象数组

Question

不确定我能做到这一点，但我想做的是通过搜索一些 JSON 数据来查找 key 来创建一个新数组，如果找到 key ，则将整个对象放入新数组中。以下是我正在使用的数据示例。

{
  "students": {
    "AB10001": {
      "campus": "cda",
      "subjects": ["history", "english"],
    }
    "AB10002": {
      "campus": "asd",
      "subjects": ["maths"],
    }
    "AB10003": {
      "campus": "asd",
      "subjects": ["english"],
    }
    "AB10004": {
      "campus": "asd",
      "subjects": ["history"],
    }
    "AB10005": {
      "campus": "cda",
      "subjects": ["maths", "science"],
    }
    "AB10006": {
      "campus": "asd",
      "subjects": ["science"],
    }
    "AB10007": {
      "campus": "cda",
      "subjects": ["science"],
    }
    "AB10008": {
      "campus": "asd",
      "subjects": ["science", "history"],
    }
    "AB10009": {
      "campus": "cda",
      "subjects": ["history"],
    }
    "AB10010": {
      "campus": "cda",
      "subjects": ["history", "maths"],
    }
  }
}

所以我想做的是搜索subjects的students键，找到所有做history的学生，然后从中创建另一个数组，获取整个学生，同时保持原始对象不变。

所以我想最终得到这样的结果:

{
  "historyStudents": {
    "AB10001": {
      "campus": "cda",
      "subjects": ["history", "english"],
    }
    "AB10004": {
      "campus": "asd",
      "subjects": ["history"],
    }
    "AB10008": {
      "campus": "asd",
      "subjects": ["science", "history"],
    }
    "AB10009": {
      "campus": "cda",
      "subjects": ["history"],
    }
    "AB10010": {
      "campus": "cda",
      "subjects": ["history", "maths"],
    }
  }
}

任何见解或帮助都会非常有帮助。提前致谢!

Answer 1

您可以使用 Object.keys() 和 reduce() 创建只有具有 history 科目的学生的新对象。

var data = {"students":{"AB10001":{"campus":"cda","subjects":["history","english"]},"AB10002":{"campus":"asd","subjects":["maths"]},"AB10003":{"campus":"asd","subjects":["english"]},"AB10004":{"campus":"asd","subjects":["history"]},"AB10005":{"campus":"cda","subjects":["maths","science"]},"AB10006":{"campus":"asd","subjects":["science"]},"AB10007":{"campus":"cda","subjects":["science"]},"AB10008":{"campus":"asd","subjects":["science","history"]},"AB10009":{"campus":"cda","subjects":["history"]},"AB10010":{"campus":"cda","subjects":["history","maths"]}}}

var result = {
 historyStudents: Object.keys(data.students)
  .reduce(function(r, e) {
    if(data.students[e].subjects.includes('history')) r[e] = data.students[e]
    return r;
   }, {})
 }

console.log(result)