Question

我有一个对象数组，它基于一个唯一属性进行组合。例如：

[
  { "macId": "123", "input": 30},
  { "macId": "567", "input": 40},
  { "macId": "123", "power": 100},
  { "macId": "567", "power": 250}
]

我希望得到的对象数组如下：

[
  { "macId": "123", "input": 30, "power": 100},
  { "macId": "567", "input": 40 "power": 250}
]

这可以用 lodash 吗？如果没有，我怎么能为此编写一个简短的代码呢？

Answer 1

使用lodash我会尝试使用macId groupBy，然后使用merge“组合”结果数组中的对象。

const after = 
  _(before)
    .groupBy('macId')
    .map(group => _.merge(...group))
    .value();

Answer 2

我建议将ES6 Map与Object.assign结合使用：

＆＃13;

const arr = [
    { "macId": "123", "input": 30},
    { "macId": "567", "input": 40},
    { "macId": "123", "power": 100},
    { "macId": "567", "power": 250}
]

const result = [...arr.reduce((acc, obj) =>
    acc.set(obj.macId, Object.assign(acc.get(obj.macId) || {}, obj)), new Map).values()];

console.log(result);

＆＃13;

.as-console-wrapper { max-height: 100% !important; top: 0; }

＆＃13;

Answer 3

您可以使用Object#assign和Array#find执行以下操作：

var myMergedArray = arr.reduce((acc = [], val) => {
  if (acc.filter(obj => obj.macId === val.macId).length !== 0) {
    Object.assign(acc.find((el) => el.macId === val.macId), val)
  } else {
    acc.push(val);
  }
  return acc;
}, [])

摘录：

＆＃13;

var arr = [
  { "macId": "123", "input": 30},
  { "macId": "567", "input": 40},
  { "macId": "123", "power": 100},
  { "macId": "567", "power": 250}
]

var myMergedArray = arr.reduce((acc = [], val) => {
  if (acc.filter(obj => obj.macId === val.macId).length !== 0) {
    Object.assign(acc.find((el) => el.macId === val.macId), val)
  } else {
    acc.push(val);
  }
  return acc;
}, [])

console.log(myMergedArray);

＆＃13;

Answer 4

由于您已标记lodash，因此您可以轻松地对其进行分组并将其映射回来（使用reduce或_.merge合并）。

var arr = [
  { "macId": "123", "input": 30},
  { "macId": "567", "input": 40},
  { "macId": "123", "power": 100},
  { "macId": "567", "power": 250}
]

var unique = _.chain(arr).groupBy('macId').map(v => _.merge(...v)).value();

console.log(unique)

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.4/lodash.js"></script>

通过唯一属性组合单个对象数组

4 个答案: