javascript - 如何像这样对对象数组进行分组？并删除重复项？

Question

我正在编写一小段具有数组的 JS 代码:

[
 { title: 'title1', id: 1 },
 { title: 'title1', id: 2 },
 { title: 'title2', id: 3},
 { title: 'title2', id: 4}
]

不过我需要这样的东西:

"queried": {
    "title1": [1, 2],
    "title2": [3, 4],
 }

我正在尝试使用 Lodash 和 _.groupBy(array, "title") 来做到这一点，但我得到:

{ 
 title1:[
  { title: 'title1', id: 1 },
  { title: 'title1', id: 2 }
],
 title2:[
  { title: 'title2', id: 3 },
  { title: 'title2', id: 4 }
],
}

请问如何解决？

Answer 1

使用_.mapValues()迭代组，_.map()提取 id 的值:

const lol = [{"title":"title1","id":1},{"title":"title1","id":2},{"title":"title2","id":3},{"title":"title2","id":4}];
  
const result = _.mapValues(
  _.groupBy(lol, 'title'),
  v => _.map(v, 'id')
);

console.log(result);

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.11/lodash.min.js"></script>