将一个数组值复制到其他数组答案

【问题标题】：Copy one array values to the the others将一个数组值复制到其他数组
【发布时间】：2018-12-06 07:52:19
【问题描述】：

我有以下 JSON 数组。我想为另一个rooms 的schedules 中不存在的dayOfWeek 设置时间表

const data = {
  rooms: [
    {
      roomId: 1,
      schedules: []
    },
    {
      roomId: 2,
      schedules: [
        { home1: "05:05", dayOfWeek: 1, away: "20:30" },
        { home1: "06:05", dayOfWeek: 5, away: "21:30" },
        { home1: "07:05", dayOfWeek: 7, away: "22:30" }
      ]
    },
    {
      roomId: 3,
      schedules: []
    }
  ]
}

我也需要将相同的时间表复制到其他房间。

预期输出

const finalArray = [
  { home1: "05:05", dayOfWeek: 1, away: "20:30", roomId: 1 }, //schedules from room2
  { home1: "06:05", dayOfWeek: 5, away: "21:30", roomId: 1 }, //schedules from room2
  { home1: "07:05", dayOfWeek: 7, away: "22:30", roomId: 1 }, //schedules from room2 

  { home1: "05:05", dayOfWeek: 1, away: "20:30", roomId: 3 }, //schedules from room2
  { home1: "06:05", dayOfWeek: 5, away: "21:30", roomId: 3 }, //schedules from room2
  { home1: "07:05", dayOfWeek: 7, away: "22:30", roomId: 3 }, //schedules from room2 
]

我试过了，但是没成功！！！请帮忙！！！

【问题讨论】：

最终数组应该是新数组还是房间数组？还是要将 roomId2 中的日程表复制到其他房间日程表数组中？
@JustAMicrobe 它是一个新数组。
那么如何处理包含时间表的那个？
@CodeManiac 需要复制到其他房间的时间表。包含roomId。请查看finalArray
好吧，你没有在 finalArray 中添加 roomId 2 吗？

标签： javascript arrays loops lodash

【解决方案1】：

您可以先找到source of truth room，然后使用Array.reduce 提取/复制时间表给其他人：

const data = { rooms: [ { roomId: 1, schedules: [] }, { roomId: 2, schedules: [ { home1: "05:05", dayOfWeek: 1, away: "20:30" }, { home1: "06:05", dayOfWeek: 5, away: "21:30" }, { home1: "07:05", dayOfWeek: 7, away: "22:30" } ] }, { roomId: 3, schedules: [] } ] }

const theRoom = data.rooms.find(x => x.schedules.length)
const result = data.rooms.reduce((r,{roomId, schedules}) => {
  if(roomId != theRoom.roomId)
     r.push(...theRoom.schedules.map(x => ({ roomId, ...x })))
  return r
}, [])
console.log(result)

【讨论】：

array.reduce(argument, argument) 中的参数是什么？

【解决方案2】：

如果您想简单地将其放入新数组中，只需这样做：

var schedular = data.rooms[1].schedules

【讨论】：

【解决方案3】：

只需遍历数组即可。

已编辑：由评论编辑

const data = {
  rooms: [
    {
      roomId: 1,
      schedules: []
    },
    {
      roomId: 2,
      schedules: [
        { home1: "05:05", dayOfWeek: 1, away: "20:30" },
        { home1: "06:05", dayOfWeek: 5, away: "21:30" },
        { home1: "07:05", dayOfWeek: 7, away: "22:30" }
      ]
    },
    {
      roomId: 3,
      schedules: []
    }
  ]
}

var roomIdWithSchedules = null;
var schedulesOfRoomWithRoomIdWithSchedules = [];
for(var i = 0; i < data.rooms.length; i++) {
  if(data.rooms[i].schedules && data.rooms[i].schedules.length) {
    roomIdWithSchedules = data.rooms[i].roomId;
    schedulesOfRoomWithRoomIdWithSchedules = data.rooms[i].schedules.map(function(x) {
      return JSON.parse(JSON.stringify(x));
    });
    break;
  }
}

var finalArray = [];
if(roomIdWithSchedules != null) {
  for(var i = 0; i < data.rooms.length; i++) {
    if(roomIdWithSchedules === data.rooms[i].roomId) {
      continue;
    }
    
    for(var j = 0; j < schedulesOfRoomWithRoomIdWithSchedules.length; j++) {
      var item = JSON.parse(JSON.stringify(schedulesOfRoomWithRoomIdWithSchedules[j]));
      item.roomId = data.rooms[i].roomId;
      finalArray.push(item)
    }
  }
}

console.log(finalArray);

【讨论】：

我得到roomId: 2 我需要其他人roomId 即1 和3