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根据id分组数组数据

redux-reducers redux reactjs javascript

1

CraZyDroiD · 技术社区 · 5 年前

通过API调用,我收到如下响应

[
  {
    stationId: "10"
    name: "Jinbaolai"
    group: {id: "18", stationGroupName: "Ali"}
  },
  {
    stationId: "13"
    name: "Stack"
    group: {id: "18", stationGroupName: "Ali"}
  },
  {
    stationId: "20"
    name: "Overflow"
    group: {id: "19", stationGroupName: "Baba"}
  }

]

如您所见,前两条记录由同一组组成。我想把这些数据按组分组。例如,它应该是这样的

[
  {
    groupId: "18",
    groupName : "Ali",
    stations : [
                 {
                  stationId: "10",
                  name: "Jinbaolai"
                 },
                 {
                  stationId: "13",
                  name: "Stack"
                 }
               ]

  },
  {
    groupId: "19",
    groupName : "Baba",
    stations : [
                 {
                  stationId: "20",
                  name: "Overflow"
                 },
               ]

  }

]

我想在我的reducer中进行分组逻辑,在这里我还设置了问题开头显示的完整数据数组。

            case EVC_SUCCESS:
            return {
                ...state,
                chargingStations: action.evcData.chargingStations,
                chargingStationGroups: //This is where my logic should go. ('action.evcData.chargingStations' is the initial data array)
                tableLoading: false
            }

我该怎么做?我试过用 filter 但不成功。

3 回复 | 直到 5 年前

1

4

Thomas Junk 5 年前

最好的方法是 Array.prototype.reduce()

减少是一个聚合函数,在这个函数中,您可以放入一个数组中的某些内容,然后获取一个vaule。

可能有一个起始值作为我使用的最后一个参数 {} . 签名是 reduce(fn, startingValue) 哪里 fn 是一个包含两个参数的函数 aggregate 和 currentValue 最后你把总数还回来。

const groupData = (data)=> {

    return Object.values(data.reduce((group,n)=>{
    if (!group[n.group.id]){
        group[n.group.id] = {
      groupId:n.group.id,
      groupName: n.group.stationGroupName,
      stations:[]}
    } 
    group[n.group.id].stations.push({
      stationID: n.stationId,
      name: n.name
    })
    return group;
  }, {}))

}

这是 fiddle

2

1

Thahzan 5 年前

一个简单的JS算法可以帮你做到这一点

const list = [
  {
    stationId: "10",
    name: "Jinbaolai",
    group: {id: "18", stationGroupName: "Ali"}
  },
  {
    stationId: "13",
    name: "Stack",
    group: {id: "18", stationGroupName: "Ali"}
  },
  {
    stationId: "20",
    name: "Overflow",
    group: {id: "19", stationGroupName: "Baba"}
  }

];
const groups = {};

list.forEach((item) => {
  const groupId = item.group.id;
  const group = groups[groupId] || {groupId: groupId, groupName: item.group.stationGroupName, stations: []};

  group.stations.push({stationId: item.stationId, name: item.name});
  groups[groupId] = group;
});

const groupedArray = Object.keys(groups).map((groupId) => groups[groupId]);

console.log(groupedArray); // This will be the output you want

3

0

Arjun Kava 5 年前

我认为链接多个函数是可行的。

const stations = [
  {
    "stationId": 10,
    "name": "Jinbaolai",
    "group": {"id": "18", "stationGroupName": "Ali"}
  },
  {
    "stationId": 13,
    "name": "Stack",
    "group": {"id": 18, "stationGroupName": "Ali"}
  },
  {
    "stationId": 20,
    "name": "Overflow",
    "group": {"id": "19", "stationGroupName": "Baba"}
  }
]
const groups = _.chain(stations)
.groupBy((station) => { return station.group.id })
.map((values, key) => { 
  return {
    "groupId": _.first(values).group.id,
    "groupName": _.first(values).group.id,
    "stations": _.map(values,(value)=>{ return { "stationId": value.stationId, "name": value.name   } })
  }
})
console.log("groups",groups)

<script src="https://cdn.jsdelivr.net/npm/lodash@4.17.15/lodash.min.js"></script>