javascript - 按 id 对 JavaScript 对象进行分组

Question

我有一个 JavaScript 对象

我试图按 id 对这些对象进行分组，并生成一个名称列表的映射，其中键是 id，值是名称。示例:

{1 : [John, Jane, Mike], 3: [Bob, Will]}

通过下面的代码，我得到:

{1: [John, Jane, Mike, Bob, Will], 3: [John, Jane, Mike, Bob, Will]}

如何才能达到我想要的输出？任何帮助将不胜感激。

var myObj = [{
    id: 1,
    name: "John",
    major: "accounting"
  },
  {
    id: 1,
    name: "Jane",
    major: "accounting"
  }, {
    id: 1,
    name: "Mike",
    major: "accounting"
  }, {
    id: 3,
    name: "Bob",
    major: "history"
  }, {
    id: 3,
    name: "Will",
    major: "history"
  }]



for (i in myObj) {
  var obj = myObj[i];
  var id = obj.id;
  var name = obj.name;
  var newMap = {};
  var namesArray = [];

  if (!(id in newMap)) {
    namesArray.push(name);
    newMap[id] = namesArray;

  } else {
    for (key in newMap) {
      if (key == id) {
        namesArray.push(name);
        newMap[key] = namesArray;
      }
    }
  }
  console.log(newMap);
}

Answer 1

编辑您自己的程序:

var myObj = [{
    id: 1,
    name: "John",
    major: "accounting"
  },
  {
    id: 1,
    name: "Jane",
    major: "accounting"
  }, {
    id: 1,
    name: "Mike",
    major: "accounting"
  }, {
    id: 3,
    name: "Bob",
    major: "history"
  }, {
    id: 3,
    name: "Will",
    major: "history"
  }]


  var newMap = {};
  var namesArray = [];
     
for (i in myObj) {
  var obj = myObj[i];
  var id = obj.id;
  var name = obj.name;

  if (!(id in newMap)) {
     namesArray = [];
     namesArray.push(name);
    newMap[id] = namesArray;

  } else {
        namesArray = newMap[id];
        namesArray.push(name);
     
  }
  
}
console.log(newMap);