Question

我收到这样的数组：

[
  { league: {id: 2, name: "champions league"}, event: "psg - varsovia", scoreteam1: 1, scoreteam:2},
  { league: {id: 5, name: "world cup"} , event: "belgium - england", scoreteam1: 1, scoreteam:2},
  { league: {id: 2, name: "champions league"}, event: "madrid - fc bruge", scoreteam1: 3, scoreteam:2},
  { league: {id: 2, name: "champions league"}, event: "milan - dortmund", scoreteam1: 1, scoreteam:2},
  { league: {id: 5, name: "world cup"} , event: "japan - danemark", scoreteam1: 1, scoreteam:5}
]

，我想获得一个新的数组，其中将同一联盟的所有事件分组在一起。最好的方法是什么？

[ 
  { 
   name: "champions league", id: 2, 
   events: 
   [ 
    {"psg - varsovia", scoreteam1: 1, scoreteam:2}, 
    {"milan - dortmund", scoreteam1: 1, scoreteam:2 }, 
    {"madrid - fc bruge", scoreteam1: 3, scoreteam:2}
   ]
  },
  { 
   name: "world cup", id: 5, 
   events: 
   [ 
    {"belgium - england", scoreteam1: 1, scoreteam:2}, 
    {"japan - danemark", scoreteam1: 1, scoreteam:5}
   ]
  }
]

我已经做到了，但是我认为它很冗长：

                     function compareCompetitionId(leagueId, item) {
                            return leagueId === item.competition.id;
                        }
                        function containCompetitionId(leagueId, items) {
                            return items.some(compareCompetitionId.bind(null, leagueId));
                        }
                        function groupByCompetitionId(memo, item) {
                            var leagueId = memo.filter(containCompetitionId.bind(null, item.competition.id));
                            if (leagueId.length > 0) {
                                leagueId[0].push(item);
                            } else {
                                memo.push([item]);
                            }
                            return memo;
                        }
                        // accumulateur
                        var results = list.reduce(groupByCompetitionId, []);
                        console.log(results)

Answer 1

您需要遍历对象数组，然后检查每个对象的属性。

进行迭代时，您会发现是否已经添加了新对象（具有所需结构的对象）来寻找id，如果是，则将事件添加到events数组中，如果否，请创建一个新对象，然后将其推入所需的结果数组。

let arr = [
  { league: {id: 2, name: "champions league"}, event: "psg - varsovia", scoreteam1: 1, scoreteam:2},
  { league: {id: 5, name: "world cup"} , event: "belgium - england", scoreteam1: 1, scoreteam:2},
  { league: {id: 2, name: "champions league"}, event: "madrid - fc bruge", scoreteam1: 3, scoreteam:2},
  { league: {id: 2, name: "champions league"}, event: "milan - dortmund", scoreteam1: 1, scoreteam:2},
  { league: {id: 5, name: "world cup"} , event: "japan - danemark", scoreteam1: 1, scoreteam:5}
]
let resultArr = []

for (var obj of arr){
  if (obj.hasOwnProperty("league")){
    if (obj.league.hasOwnProperty("id") && obj.league.hasOwnProperty("name")){
      let existObj = resultArr.find(x => x.id == obj.league.id)
      if (existObj == null){
        let newObj = {}
        newObj.name = obj.league.name
        newObj.id = obj.league.id
        newObj.events = []
        if (obj.hasOwnProperty("event")){
          let event = {}
          event.teams = obj.event;
          event.scoreteam1 = obj.scoreteam1;
          event.scoreteam2 = obj.scoreteam;
          newObj.events.push(event)
        }
        resultArr.push(newObj)
      }
      else{
        if (!existObj.hasOwnProperty("events")){
          existObj.events = []
        }
        let event = {}
        event.teams = obj.event;
        event.scoreteam1 = obj.scoreteam1;
        event.scoreteam2 = obj.scoreteam;
        existObj.events.push(event)
      }
    }
  }
}
console.log(resultArr)

在javascript中对数组进行排序

1 个答案: