javascript 如何按日期对数组中的项目进行分组？
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How do I group items in an array by date?
提问by Blake
Given the following array of objects:
给定以下对象数组：
[
{
"notes": "Game was played",
"time": "2017-10-04T20:24:30+00:00",
"sport": "hockey",
"owner": "steve",
"players": "10",
"game_id": 1,
},
{
"notes": "Game was played",
"time": "2017-10-04T12:35:30+00:00",
"sport": "lacrosse",
"owner": "steve",
"players": "6",
"game_id": 2,
},
{
"notes": "Game was played",
"time": "2017-10-14T20:32:30+00:00",
"sport": "hockey",
"owner": "steve",
"players": "4",
"game_id": 3,
},
{
"notes": "Game was played",
"time": "2017-10-04T10:12:30+00:00",
"sport": "hockey",
"owner": "henry",
"players": "10",
"game_id": 4,
},
{
"notes": "Game was played",
"time": "2017-10-14T20:34:30+00:00",
"sport": "soccer",
"owner": "john",
"players": "12",
"game_id": 5,
}
]
I am trying to create a new array, that would create an object with each date(as a key) and any games played on that date listed under games(another key) in the same object.
我正在尝试创建一个新数组，它将创建一个对象，其中每个日期（作为键）以及在同一对象中的游戏（另一个键）下列出的该日期玩的任何游戏。
The new array should look like:
新数组应如下所示：
[
{
date:'date string',
games:[array of games played on the date]
},
{
date: 'other date',
games:[games under the other date]
}
]...
Here is what I have done:
这是我所做的：
let t = this.state.data; (data above)
let list = [];
for (let i = 0; i < t.length; i++) {
let dates = t[i].time.slice(0,10);
if (!list[dates]) {
list[dates] = [];
}
list[dates].push(t[i]);
}
My version returns a array with the dates as the values, and then inside of those the games are listed, but i am trying to list them in the same object as different keys.
我的版本返回一个以日期为值的数组，然后在其中列出游戏，但我试图将它们作为不同的键列在同一个对象中。
Any help or guidance would be greatly appreciated.
任何帮助或指导将不胜感激。
回答by Austin Greco
Here's a solution using reduce. Split the timeinto a date string, and then set a key for each date. If the key exists push it onto the array:
这是使用reduce. 将其拆分time为日期字符串，然后为每个日期设置一个键。如果键存在，则将其推入数组：
Updateadded the array format version
更新添加了数组格式版本
const data = [
{notes: 'Game was played', time: '2017-10-04T20:24:30+00:00', sport: 'hockey', owner: 'steve', players: '10', game_id: 1},
{ notes: 'Game was played', time: '2017-10-04T12:35:30+00:00', sport: 'lacrosse', owner: 'steve', players: '6', game_id: 2 },
{ notes: 'Game was played', time: '2017-10-14T20:32:30+00:00', sport: 'hockey', owner: 'steve', players: '4', game_id: 3 },
{ notes: 'Game was played', time: '2017-10-04T10:12:30+00:00', sport: 'hockey', owner: 'henry', players: '10', game_id: 4 },
{ notes: 'Game was played', time: '2017-10-14T20:34:30+00:00', sport: 'soccer', owner: 'john', players: '12', game_id: 5 }
];
// this gives an object with dates as keys
const groups = data.reduce((groups, game) => {
const date = game.time.split('T')[0];
if (!groups[date]) {
groups[date] = [];
}
groups[date].push(game);
return groups;
}, {});
// Edit: to add it in the array format instead
const groupArrays = Object.keys(groups).map((date) => {
return {
date,
games: groups[date]
};
});
console.log(groupArrays);回答by bobbyanne
Is this what you're looking for???
这是你要找的？？？
var data = [
{
notes: 'Game was played',
time: '2017-10-04T20:24:30+00:00',
sport: 'hockey',
owner: 'steve',
players: '10',
game_id: 1
},
{
notes: 'Game was played',
time: '2017-10-04T12:35:30+00:00',
sport: 'lacrosse',
owner: 'steve',
players: '6',
game_id: 2
},
{
notes: 'Game was played',
time: '2017-10-14T20:32:30+00:00',
sport: 'hockey',
owner: 'steve',
players: '4',
game_id: 3
},
{
notes: 'Game was played',
time: '2017-10-04T10:12:30+00:00',
sport: 'hockey',
owner: 'henry',
players: '10',
game_id: 4
},
{
notes: 'Game was played',
time: '2017-10-14T20:34:30+00:00',
sport: 'soccer',
owner: 'john',
players: '12',
game_id: 5
}
];
function extract() {
var groups = {};
data.forEach(function(val) {
var date = val.time.split('T')[0];
if (date in groups) {
groups[date].push(val.sport);
} else {
groups[date] = new Array(val.sport);
}
});
console.log(groups);
return groups;
}
extract();回答by Prasanna
let a =[{
"notes": "Game was played",
"time": "2017-10-04T20:24:30+00:00",
"sport": "hockey",
"owner": "steve",
"players": "10",
"game_id": 1,
},
{
"notes": "Game was played",
"time": "2017-10-04T12:35:30+00:00",
"sport": "lacrosse",
"owner": "steve",
"players": "6",
"game_id": 2,
},
{
"notes": "Game was played",
"time": "2017-10-14T20:32:30+00:00",
"sport": "hockey",
"owner": "steve",
"players": "4",
"game_id": 3,
},
{
"notes": "Game was played",
"time": "2017-10-04T10:12:30+00:00",
"sport": "hockey",
"owner": "henry",
"players": "10",
"game_id": 4,
},
{
"notes": "Game was played",
"time": "2017-10-14T20:34:30+00:00",
"sport": "soccer",
"owner": "john",
"players": "12",
"game_id": 5,
}]
let finalObj = {}
a.forEach((games) => {
const date = games.time.split('T')[0]
if (finalObj[date]) {
finalObj[date].push(games);
} else {
finalObj[date] = [games];
}
})
console.log(finalObj)