Question

我有一个JSON文件，我希望根据其中的三个字段对该JSON进行分组。

JSON如下（当然还有更多内容）：

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<div class="form-group row">
  <select name="count_pax" id="count_paxx" class="form-control col-md-9" />
  <option value="">Select how many people</option>
  <option value="1">1 pax</option>
  <option value="2">2 pax</option>
  <option value="3">3 pax</option>
  <option value="4">4 pax</option>
  <option value="5">5 pax</option>
  <option value="6">6 pax</option>
  <option value="7">7 pax</option>
  <option value="8">8 pax</option>
  <option value="9">9 pax</option>
  <option value="10">10 pax</option>
  <option value="11">11 pax</option>
  <option value="12">12 pax</option>
  </select>
</div>
<div class="form-group row" id="demo_paxx">
</div>

请求的结果（使用switch result.rawValue { case MFMailComposeResult.cancelled.rawValue: print("Mail cancelled") case MFMailComposeResult.saved.rawValue: print("Mail saved") case MFMailComposeResult.sent.rawValue: print("Mail sent") case MFMailComposeResult.failed.rawValue: print("Mail sent failure: \(error?.localizedDescription)") default: break }或{ "Racename": "10KM", "Category": 34, "Gender": "Male", "Work": "Google", "FullName": "Dave Happner", "Rank": 1, "Ponit": 1, "Numparticipant": 0, "rankparticipant": 0, "precentagePart": "0", "NumRaces": 1, "RaceTime": "2018-10-18T00:34:20", "rankCat": 1, "PointCat": 1, "RaceDate": "2018-10-05" }）是：

underscore

Answer 1

您可以reduce进入由字符串索引的对象，该字符串由Racename，Category和Gender组成，并由一个不会存在于值中，例如_。例如，您在问题中的输入将导致键为10KM_34_Male的对象。在每次迭代中，检查构造的键是否存在-如果不存在，则使用空的runner数组创建对象。然后，推送到runner数组。

完成reduce之后，您可以获取对象的值以获取所需的数组输出：

const input = [{
  "Racename": "10KM",
  "Category": 34,
  "Gender": "Male",
  "Work": "Google",
  "FullName": "Dave Happner",
  "Rank": 1,
  "Ponit": 1,
  "Numparticipant": 0,
  "rankparticipant": 0,
  "precentagePart": "0",
  "NumRaces": 1,
  "RaceTime": "2018-10-18T00:34:20",
  "rankCat": 1,
  "PointCat": 1,
  "RaceDate": "2018-10-05"
}];

const outputObj = input.reduce((a, { Racename, Category, Gender, ...rest }) => {
  const key = [Racename, Category, Gender].join('_');
  if (!a[key]) {
    a[key] = { Racename, Category, Gender, runner: [] };
  }
  a[key].runner.push(rest);
  return a;
}, {});
const output = Object.values(outputObj);
console.log(output);

或者，使用更大的输入：

const input = [{
  "Racename": "10KM",
  "Category": 34,
  "Gender": "Male",
  "Work": "Google",
  "FullName": "Dave Happner",
  "Rank": 1,
  "Ponit": 1,
  "Numparticipant": 0,
  "rankparticipant": 0,
  "precentagePart": "0",
  "NumRaces": 1,
  "RaceTime": "2018-10-18T00:34:20",
  "rankCat": 1,
  "PointCat": 1,
  "RaceDate": "2018-10-05"
},{
  "Racename": "10KM",
  "Category": 34,
  "Gender": "Male",
  "Work": "Amazon",
  "FullName": "Bob Joe",
  "Rank": 12,
  "Ponit": 2,
  "Numparticipant": 0,
  "rankparticipant": 0,
  "precentagePart": "0",
  "NumRaces": 1,
  "RaceTime": "2018-10-18T00:34:20",
  "rankCat": 1,
  "PointCat": 1,
  "RaceDate": "2018-10-05"
},{
  "Racename": "20KM",
  "Category": 40,
  "Gender": "Male",
  "Work": "Google",
  "FullName": "Dave Happner",
  "Rank": 1,
  "Ponit": 1,
  "Numparticipant": 0,
  "rankparticipant": 0,
  "precentagePart": "0",
  "NumRaces": 1,
  "RaceTime": "2018-10-18T00:34:20",
  "rankCat": 1,
  "PointCat": 1,
  "RaceDate": "2018-10-05"
}
];

const outputObj = input.reduce((a, { Racename, Category, Gender, ...rest }) => {
  const key = [Racename, Category, Gender].join('_');
  if (!a[key]) {
    a[key] = { Racename, Category, Gender, runner: [] };
  }
  a[key].runner.push(rest);
  return a;
}, {});
const output = Object.values(outputObj);
console.log(output);

按数组分组

1 个答案: