javascript - 两个集合形成一个集合，用更新的字段替换重复项

Question

我有两个独特的集合，看起来像这样:

集合一:

[
 {
  id: 123,
  Name: Ben,
  Type: Car 
 },
 {
  id: 124,
  Name: Morgan,
  Type: Van
 },
 {
  id: 125,
  Name: Josh,
  Type: Bus
 }
]

集合二:

[
 {
  id: 123,
  Name: Ben,
  Type: House
 },
 {
  id: 124,
  Name: Morgan,
  Type: Flat
 },
 {
  id: 126,
  Name: Jack,
  Type: Landrover
 }
]

我已使用 lodash _.uinqBy 确保两个集合中没有重复项。

但是，我想将两者合并在一起以创建一个集合，但将具有匹配 id 的集合替换为类型为 === "Car"|| 的集合===“货车”

因此，我从上述集合中得到的结果将是:

结果:

[
 {
  id: 123,
  Name: Ben,
  Type: Car 
 },
 {
  id: 124,
  Name: Morgan,
  Type: Van
 },
 {
  id: 125,
  Name: Josh,
  Type: Bus
 },
 {
  id: 126,
  Name: Jack,
  Type: Landrover
 }
]

无论如何，我可以使用 lodash 来做到这一点吗？或者有其他方式吗？

提前致谢:)

Answer 1

使用洛达什:

function unite(arr1, arr2) {
  return _(arr1)
    .concat(arr2) // concat the arrays
    .groupBy('id') // create a group by the id
    .map(function(group) { // in each group
      return _.find(group, function(item) { // find if one contains the request Type, and if not return the 1st in the group
        return item.Type === 'Car' || item.Type === 'Van'; 
      }) || _.head(group);
    })
    .values() // exract the values
    .value();
}

function unite(arr1, arr2) {
  return _(arr1)
    .concat(arr2) // concat the arrays
    .groupBy('id') // create a group by the id
    .map(function(group) { // in each group
      return _.find(group, function(item) { // find if one contains the request Type, and if not return the 1st in the group
        return item.Type === 'Car' || item.Type === 'Van'; 
      }) || _.head(group);
    })
    .values() // exract the values
    .value();
}

var arr1 = [{
  id: '123',
  Name: 'Ben',
  Type: 'Car'
}, {
  id: '124',
  Name: 'Morgan',
  Type: 'Flat'
}, {
  id: '125',
  Name: 'Josh',
  Type: 'Bus'
}];

var arr2 = [{
  id: '123',
  Name: 'Ben',
  Type: 'House'
}, {
  id: '124',
  Name: 'Morgan',
  Type: 'Van'
}, {
  id: '126',
  Name: 'Jack',
  Type: 'Landrover'
}];

var result = unite(arr1, arr2);

console.log(result);

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.2/lodash.min.js"></script>

使用 ES6 Map 和传播:

const uniqueUnion = (arr1, arr2) => [
  ...arr1.concat(arr2)
  .reduce((m, item) => {
    if(!m.has(item.id) || item.Type === 'Car' || item.Type === 'Van') {
      m.set(item.id, item);
    }

    return m;
  }, new Map()).values()
];

const unite = (arr1, arr2) => [
  ...arr1.concat(arr2)
  .reduce((m, item) => {
    if (!m.has(item.id) || item.Type === 'Car' || item.Type === 'Van') {
      m.set(item.id, item);
    }

    return m;
  }, new Map()).values()
];

const arr1 = [{
  id: '123',
  Name: 'Ben',
  Type: 'Car'
}, {
  id: '124',
  Name: 'Morgan',
  Type: 'Flat'
}, {
  id: '125',
  Name: 'Josh',
  Type: 'Bus'
}];

const arr2 = [{
  id: '123',
  Name: 'Ben',
  Type: 'House'
}, {
  id: '124',
  Name: 'Morgan',
  Type: 'Van'
}, {
  id: '126',
  Name: 'Jack',
  Type: 'Landrover'
}];

const result = unite(arr1, arr2);

console.log(result);