Question

我有一个对象数组，我想使用Reduce转换为对象：

const results = [{
    person: "person1",
    choice: 0,
    questionId: "a"
  },
  {
    person: "person1",
    choice: 1,
    questionId: "b"
  },
  {
    ...
  }
];

并希望返回具有此预期输出的对象：

    {
      results: [
        person1: {
          a: [1, 0, 0, 0],
          b: [0, 1, 0, 0],
          c: [0, 0, 0, 0]
        },
        person2: {
          a: [0, 0, 0, 0],
          b: [0, 0, 1, 0],
          c: [0, 1, 0, 0]
        },
        person3: {
          a: [0, 0, 0, 1],
          b: [0, 0, 0, 0],
          c: [0, 0, 0, 0]
        }
      ]
    }

每个a：[...]指的是＆＃34;选择＆＃34; [0,1,2,3]每个＆＃34;问题＆＃34; [A，B，C]。 Person应该是索引，而questionId可能是变量的（它可能包括＆＃34; d＆＃34;例如＆＃34;）。

我的尝试：

＆＃13;

        const results = [{
person: "person1",
choice: 0,
questionId: "a"
  },
  {
person: "person1",
choice: 1,
questionId: "b"
  },
  {
person: "person2",
choice: 2,
questionId: "c"
  },
  {
person: "person2",
choice: 3,
questionId: "b"
  },
  {
person: "person3",
choice: 2,
questionId: "a"
  }
]; 

people = ["person1", "person2", "person3"];

let responses = results.reduce((init, response) => {
      switch (response.segment) {
        case people[0]:
          init[people[0]][response.questionId].push(response.choice[0])
          break;
        case people[1]:
          init[people[1]][response.questionId].push(response.choice[0])
          break;
          case people[2]:
          init[people[2]][response.questionId].push(response.choice[0]);
          break;
            default:
            	break;
          }
		return init;
      });
      
console.log(responses);

＆＃13;

我不确定如何启动对象以允许附加问题并获得我需要的格式？

非常感谢。

Answer 1

假设在您的输出中，您的意思是{ "person1": {...}, ...}而不是[ "person1": {...}, ...]（后者是语法错误），您可以使用reduce执行此操作，如下所示：

＆＃13;

const results = [
  { person: "person1", choice: 0, questionId: "a" },
  { person: "person1", choice: 1, questionId: "b" },
  { person: "person2", choice: 2, questionId: "c" },
  { person: "person2", choice: 3, questionId: "b" },
  { person: "person3", choice: 2, questionId: "a" }
]; 

// create an array of all unique questionIds found in the results array
var questionIds = Array.from(new Set(results.map(result => result.questionId)));
console.log(questionIds);

var resultsObj = {
  results: results.reduce((res, {person, questionId, choice}) => {
    // if person hasn't been created yet, create them
    if (!res[person]) {
      // need to do .map here instead of outside so we get fresh array references for each person
      res[person] = Object.assign({}, ...questionIds.map(id => ({[id]: [0,0,0,0]})));
    }
    // log a 1 in the correct slot for the answer given
    res[person][questionId][choice] = 1;
    return res;
  }, {})
};

console.log(resultsObj);

＆＃13;

使用Reduce嵌套嵌套对象

1 个答案: