问题描述
我有以下对象:
[
{ createdAt: "08-08-2020,12:04:19 am",id: "1" },{ createdAt: "08-08-2020,id: "2" },{ createdAt: "08-10-2020,id: "3" },id: "4" },{ createdAt: "08-12-2020,id: "5" },{ createdAt: "08-20-2020,id: "6" }
]
如您所见,每个数组都有一个创建日期和一个特定值。我想在这里创建一个看起来像这样的新对象:
[
{ createdAt: "08-08-2020",ids: ["1","2"] },{ createdAt: "08-10-2020",ids: ["3","4"] },{ createdAt: "08-12-2020",ids: ["5"] },{ createdAt: "08-20-2020",ids: ["6" ]}
]
基本上按照创建日期排列ID。我一直在尝试使用ECMA6对此进行过滤和映射,但是对我来说逻辑尚不清楚。
任何帮助将不胜感激。
谢谢!
解决方法
首先,在createdAt和id之间创建一个映射
const array = [
{ createdAt: "08-08-2020,12:04:19 am",id: "1" },{ createdAt: "08-08-2020,id: "2" },{ createdAt: "08-10-2020,id: "3" },id: "4" },{ createdAt: "08-12-2020,id: "5" },{ createdAt: "08-20-2020,id: "6" }
]
const map = {}
array.forEach(item => {
if (map[item.createdAt] === undefined) {
map[item.createdAt] = []
}
map[item.createdAt].push(item.id)
})
然后,将地图重新排列为数组:
const resultingArray = Object.entries(map).map(([createdAt,ids]) => ({
createdAt,ids
}))
,
这可以通过基本的reduce
操作来完成,该操作使用对象将具有相同日期的元素分组。
const arr = [
{ createdAt: "08-08-2020,id: "6" }
];
const res = Object.values(
arr.reduce((acc,{createdAt,id})=>{
const date = createdAt.split(",")[0];
acc[date] = acc[date] || {createdAt: date,ids: []};
acc[date].ids.push(id);
return acc;
},{})
);
console.log(res);