我有一组具有多个键值对的对象,我需要根据'updated_at'对它们进行排序:
[
{
"updated_at" : "2012-01-01T06:25:24Z",
"foo" : "bar"
},
{
"updated_at" : "2012-01-09T11:25:13Z",
"foo" : "bar"
},
{
"updated_at" : "2012-01-05T04:13:24Z",
"foo" : "bar"
}
]
最有效的方法是什么?
答案 0 :(得分:286)
您可以使用Array.sort
。
这是一个(未经测试的)示例:
arr.sort(function(a, b){
var keyA = new Date(a.updated_at),
keyB = new Date(b.updated_at);
// Compare the 2 dates
if(keyA < keyB) return -1;
if(keyA > keyB) return 1;
return 0;
});
答案 1 :(得分:146)
我已在这里回答了一个非常类似的问题:Simple function to sort an array of objects
对于那个问题,我创建了这个可能做你想做的小功能:
function sortByKey(array, key) {
return array.sort(function(a, b) {
var x = a[key]; var y = b[key];
return ((x < y) ? -1 : ((x > y) ? 1 : 0));
});
}
答案 2 :(得分:19)
Array.sort()方法对数组中的元素进行排序并返回数组。请注意Array.sort(),因为它不是Immutable。对于不可变排序,请使用immutable-sort。
此方法是使用ISO格式的当前updated_at
对数组进行排序。我们使用new Data(iso_string).getTime()
将ISO时间转换为Unix时间戳。 Unix时间戳是一个我们可以进行简单数学运算的数字。我们减去结果的第一个和第二个时间戳;如果第一个时间戳大于第二个时间戳,则返回数字为正数。如果第二个数字大于第一个数字,则返回值将为负数。如果两者相同,则返回值为零。这完全符合内联函数所需的返回值。
ES6:
arr.sort((a,b) => new Date(a.updated_at).getTime() - new Date(b.updated_at).getTime());
ES5:
arr.sort(function(a,b){
return new Date(a.updated_at).getTime() - new Date(b.updated_at).getTime();
});
如果您将updated_at
更改为unix时间戳,则可以执行以下操作:
ES6:
arr.sort((a,b) => a.updated_at - b.updated_at);
ES5:
arr.sort(function(a,b){
return a.updated_at - b.updated_at;
});
在本文发表时,现代浏览器不支持ES6。要在现代浏览器中使用ES6,请使用babel将代码转换为ES5。预计在不久的将来浏览器支持ES6。
Array.sort()应该收到3种可能结果之一的返回值:
请注意,内联函数的返回值可以是任意值 正数或负数。 Array.Sort()并不关心什么 返回号码是。它只关心返回值是否为正数, 否定或为零。
对于不可变排序:( ES6中的示例)
const sort = require('immutable-sort');
const array = [1, 5, 2, 4, 3];
const sortedArray = sort(array);
您也可以这样写:
import sort from 'immutable-sort';
const array = [1, 5, 2, 4, 3];
const sortedArray = sort(array);
您看到的导入是一种在ES6中包含javascript并使您的代码看起来非常干净的新方法。我个人的最爱。
不可变排序不会改变源数组,而是返回一个新数组。建议在不可变数据上使用const
。
答案 3 :(得分:18)
这是@David Brainer-Bankers answer的略微修改版本,按字母顺序按字母顺序排序,或按数字按数字排序,并确保以大写字母开头的单词不会以小写字母开头的单词排序(例如“apple”,早期“将按此顺序显示。”
function sortByKey(array, key) {
return array.sort(function(a, b) {
var x = a[key];
var y = b[key];
if (typeof x == "string")
{
x = (""+x).toLowerCase();
}
if (typeof y == "string")
{
y = (""+y).toLowerCase();
}
return ((x < y) ? -1 : ((x > y) ? 1 : 0));
});
}
答案 4 :(得分:13)
使用下划线js或lodash,
var arrObj = [
{
"updated_at" : "2012-01-01T06:25:24Z",
"foo" : "bar"
},
{
"updated_at" : "2012-01-09T11:25:13Z",
"foo" : "bar"
},
{
"updated_at" : "2012-01-05T04:13:24Z",
"foo" : "bar"
}
];
arrObj = _.sortBy(arrObj,"updated_at");
_.sortBy()
返回一个新数组
参考http://underscorejs.org/#sortBy和 lodash docs https://lodash.com/docs#sortBy
答案 5 :(得分:3)
在This回答状态时,您可以使用Array.sort
。
arr.sort(function(a,b){return new Date(a.updated_at) - new Date(b.updated_at)})
arr = [
{
"updated_at" : "2012-01-01T06:25:24Z",
"foo" : "bar"
},
{
"updated_at" : "2012-01-09T11:25:13Z",
"foo" : "bar"
},
{
"updated_at" : "2012-01-05T04:13:24Z",
"foo" : "bar"
}
];
arr.sort(function(a,b){return new Date(a.updated_at) - new Date(b.updated_at)});
console.log(arr);
答案 6 :(得分:2)
我在Typescript中创建了一个排序功能,我们可以使用该功能来搜索对象数组中的字符串,日期和数字。它还可以在多个字段上排序。
Allow invalid certificates for resources loaded from localhost.
用法:
export type SortType = 'string' | 'number' | 'date';
export type SortingOrder = 'asc' | 'desc';
export interface SortOptions {
sortByKey: string;
sortType?: SortType;
sortingOrder?: SortingOrder;
}
class CustomSorting {
static sortArrayOfObjects(fields: SortOptions[] = [{sortByKey: 'value', sortType: 'string', sortingOrder: 'desc'}]) {
return (a, b) => fields
.map((field) => {
if (!a[field.sortByKey] || !b[field.sortByKey]) {
return 0;
}
const direction = field.sortingOrder === 'asc' ? 1 : -1;
let firstValue;
let secondValue;
if (field.sortType === 'string') {
firstValue = a[field.sortByKey].toUpperCase();
secondValue = b[field.sortByKey].toUpperCase();
} else if (field.sortType === 'number') {
firstValue = parseInt(a[field.sortByKey], 10);
secondValue = parseInt(b[field.sortByKey], 10);
} else if (field.sortType === 'date') {
firstValue = new Date(a[field.sortByKey]);
secondValue = new Date(b[field.sortByKey]);
}
return firstValue > secondValue ? direction : firstValue < secondValue ? -(direction) : 0;
})
.reduce((pos, neg) => pos ? pos : neg, 0);
}
}
}
答案 7 :(得分:2)
通过ES2015支持,可以通过以下方式完成:
foo.sort((a, b) => a.updated_at < b.updated_at ? -1 : 1)
答案 8 :(得分:2)
另一种更多 数学 ,做同样事情的方式,但更短:
arr.sort(function(a, b){
var diff = new Date(a.updated_at) - new Date(b.updated_at);
return diff/(Math.abs(diff)||1);
});
或光滑的lambda箭头样式:
arr.sort((a, b) => {
var diff = new Date(a.updated_at) - new Date(b.updated_at);
return diff/(Math.abs(diff)||1);
});
此方法可以使用任何数字输入
答案 9 :(得分:1)
至于今天,@ knowbody(https://stackoverflow.com/a/42418963/6778546)和@Rocket Hazmat(https://stackoverflow.com/a/8837511/6778546)的答案可以结合使用,以提供ES2015支持和正确的日期处理:
arr.sort((a, b) => {
const dateA = new Date(a.updated_at);
const dateB = new Date(b.updated_at);
return dateA - dateB;
});
答案 10 :(得分:1)
已导入数据
[
{
"gameStatus": "1",
"userId": "c02cfb18-ae66-430b-9524-67d9dd8f6a50",
"created_at": "2018-12-20 11:32:04"
},
{
"gameStatus": "0",
"userId": "c02cfb18-ae66-430b-9524-67d9dd8f6a50",
"created_at": "2018-12-19 18:08:24"
},
{
"gameStatus": "2",
"userId": "c02cfb18-ae66-430b-9524-67d9dd8f6a50",
"created_at": "2018-12-19 18:35:40"
},
{
"gameStatus": "0",
"userId": "c02cfb18-ae66-430b-9524-67d9dd8f6a50",
"created_at": "2018-12-19 10:42:53"
},
{
"gameStatus": "2",
"userId": "c02cfb18-ae66-430b-9524-67d9dd8f6a50",
"created_at": "2018-12-20 10:54:09"
},
{
"gameStatus": "0",
"userId": "1a2fefb0-5ae2-47eb-82ff-d1b2cc27875a",
"created_at": "2018-12-19 18:46:22"
},
{
"gameStatus": "1",
"userId": "7118ed61-d8d9-4098-a81b-484158806d21",
"created_at": "2018-12-20 10:50:48"
}
]
用于升序
arr.sort(function(a, b){
var keyA = new Date(a.updated_at),
keyB = new Date(b.updated_at);
// Compare the 2 dates
if(keyA < keyB) return -1;
if(keyA > keyB) return 1;
return 0;
});
升序示例
[
{
"gameStatus": "0",
"userId": "c02cfb18-ae66-430b-9524-67d9dd8f6a50",
"created_at": "2018-12-19 10:42:53"
},
{
"gameStatus": "0",
"userId": "c02cfb18-ae66-430b-9524-67d9dd8f6a50",
"created_at": "2018-12-19 18:08:24"
},
{
"gameStatus": "2",
"userId": "c02cfb18-ae66-430b-9524-67d9dd8f6a50",
"created_at": "2018-12-19 18:35:40"
},
{
"gameStatus": "0",
"userId": "1a2fefb0-5ae2-47eb-82ff-d1b2cc27875a",
"created_at": "2018-12-19 18:46:22"
},
{
"gameStatus": "1",
"userId": "7118ed61-d8d9-4098-a81b-484158806d21",
"created_at": "2018-12-20 10:50:48"
},
{
"gameStatus": "2",
"userId": "c02cfb18-ae66-430b-9524-67d9dd8f6a50",
"created_at": "2018-12-20 10:54:09"
},
{
"gameStatus": "1",
"userId": "c02cfb18-ae66-430b-9524-67d9dd8f6a50",
"created_at": "2018-12-20 11:32:04"
}
]
降序
arr.sort(function(a, b){
var keyA = new Date(a.updated_at),
keyB = new Date(b.updated_at);
// Compare the 2 dates
if(keyA > keyB) return -1;
if(keyA < keyB) return 1;
return 0;
});
降序顺序示例
[
{
"gameStatus": "1",
"userId": "c02cfb18-ae66-430b-9524-67d9dd8f6a50",
"created_at": "2018-12-20 11:32:04"
},
{
"gameStatus": "2",
"userId": "c02cfb18-ae66-430b-9524-67d9dd8f6a50",
"created_at": "2018-12-20 10:54:09"
},
{
"gameStatus": "1",
"userId": "7118ed61-d8d9-4098-a81b-484158806d21",
"created_at": "2018-12-20 10:50:48"
},
{
"gameStatus": "0",
"userId": "1a2fefb0-5ae2-47eb-82ff-d1b2cc27875a",
"created_at": "2018-12-19 18:46:22"
},
{
"gameStatus": "2",
"userId": "c02cfb18-ae66-430b-9524-67d9dd8f6a50",
"created_at": "2018-12-19 18:35:40"
},
{
"gameStatus": "0",
"userId": "c02cfb18-ae66-430b-9524-67d9dd8f6a50",
"created_at": "2018-12-19 18:08:24"
},
{
"gameStatus": "0",
"userId": "c02cfb18-ae66-430b-9524-67d9dd8f6a50",
"created_at": "2018-12-19 10:42:53"
}
]
答案 11 :(得分:1)
有了这个,我们可以传递一个用于排序的键函数
password_verify()
例如,如果我们有
Array.prototype.sortBy = function(key_func, reverse=false){
return this.sort( (a, b) => {
var keyA = key_func(a),
keyB = key_func(b);
if(keyA < keyB) return reverse? 1: -1;
if(keyA > keyB) return reverse? -1: 1;
return 0;
});
}
我们可以做到
var arr = [ {date: "01/12/00", balls: {red: "a8", blue: 10}},
{date: "12/13/05", balls: {red: "d6" , blue: 11}},
{date: "03/02/04", balls: {red: "c4" , blue: 15}} ]
或
arr.sortBy(el => el.balls.red)
/* would result in
[ {date: "01/12/00", balls: {red: "a8", blue: 10}},
{date: "03/02/04", balls: {red: "c4", blue: 15}},
{date: "12/13/05", balls: {red: "d6", blue: 11}} ]
*/
或
arr.sortBy(el => new Date(el.date), true) // second argument to reverse it
/* would result in
[ {date: "12/13/05", balls: {red: "d6", blue:11}},
{date: "03/02/04", balls: {red: "c4", blue:15}},
{date: "01/12/00", balls: {red: "a8", blue:10}} ]
*/
答案 12 :(得分:1)
按ISO格式化日期排序可能很昂贵,除非您将客户端限制为最新和最好的浏览器,这可以通过日期解析字符串来创建正确的时间戳。
如果您肯定您的输入,并且知道它将始终是yyyy-mm-ddThh:mm:ss和GMT(Z)您可以提取每个成员的数字,并将它们像整数一样进行比较
array.sort(function(a,b){
return a.updated_at.replace(/\D+/g,'')-b.updated_at.replace(/\D+/g,'');
});
如果日期的格式可能不同,您可能需要为iso挑战的人添加一些内容:
Date.fromISO: function(s){
var day, tz,
rx=/^(\d{4}\-\d\d\-\d\d([tT ][\d:\.]*)?)([zZ]|([+\-])(\d\d):(\d\d))?$/,
p= rx.exec(s) || [];
if(p[1]){
day= p[1].split(/\D/).map(function(itm){
return parseInt(itm, 10) || 0;
});
day[1]-= 1;
day= new Date(Date.UTC.apply(Date, day));
if(!day.getDate()) return NaN;
if(p[5]){
tz= (parseInt(p[5], 10)*60);
if(p[6]) tz+= parseInt(p[6], 10);
if(p[4]== '+') tz*= -1;
if(tz) day.setUTCMinutes(day.getUTCMinutes()+ tz);
}
return day;
}
return NaN;
}
if(!Array.prototype.map){
Array.prototype.map= function(fun, scope){
var T= this, L= T.length, A= Array(L), i= 0;
if(typeof fun== 'function'){
while(i< L){
if(i in T){
A[i]= fun.call(scope, T[i], i, T);
}
++i;
}
return A;
}
}
}
}
答案 13 :(得分:0)
为了完整性,这里有一个可能的sortBy的简短通用实现:
function sortBy(list, keyFunc) {
return list.sort((a,b) => keyFunc(a) - keyFunc(b));
}
sortBy([{"key": 2}, {"key": 1}], o => o["key"])
请注意,这使用了在适当位置排序的数组排序方法。 对于副本,您可以使用arr.concat()或arr.slice(0)或类似方法来创建副本。
答案 14 :(得分:0)
var months = [
{
"updated_at" : "2012-01-01T06:25:24Z",
"foo" : "bar"
},
{
"updated_at" : "2012-01-09T11:25:13Z",
"foo" : "bar"
},
{
"updated_at" : "2012-01-05T04:13:24Z",
"foo" : "bar"
}];
months.sort((a, b)=>{
var keyA = new Date(a.updated_at),
keyB = new Date(b.updated_at);
// Compare the 2 dates
if(keyA < keyB) return -1;
if(keyA > keyB) return 1;
return 0;
});
console.log(months);
答案 15 :(得分:0)
您可以创建一个闭包并以这种方式传递它 here is my example working
$.get('https://data.seattle.gov/resource/3k2p-39jp.json?$limit=10&$where=within_circle(incident_location, 47.594972, -122.331518, 1609.34)',
function(responce) {
var filter = 'event_clearance_group', //sort by key group name
data = responce;
var compare = function (filter) {
return function (a,b) {
var a = a[filter],
b = b[filter];
if (a < b) {
return -1;
} else if (a > b) {
return 1;
} else {
return 0;
}
};
};
filter = compare(filter); //set filter
console.log(data.sort(filter));
});
答案 16 :(得分:0)
Array.sort()
对数组进行排序…
)克隆数组以使函数纯净updated_at
)排序Array.sort()
通过从当前项目和下一项减去两个属性(如果它是可以执行心律不齐操作的数字/对象)来工作const input = [
{
updated_at: '2012-01-01T06:25:24Z',
foo: 'bar',
},
{
updated_at: '2012-01-09T11:25:13Z',
foo: 'bar',
},
{
updated_at: '2012-01-05T04:13:24Z',
foo: 'bar',
}
];
const sortByUpdatedAt = (items) => [...items].sort((itemA, itemB) => new Date(itemA.updated_at) - new Date(itemB.updated_at));
const output = sortByUpdatedAt(input);
console.log(input);
/*
[ { updated_at: '2012-01-01T06:25:24Z', foo: 'bar' },
{ updated_at: '2012-01-09T11:25:13Z', foo: 'bar' },
{ updated_at: '2012-01-05T04:13:24Z', foo: 'bar' } ]
*/
console.log(output)
/*
[ { updated_at: '2012-01-01T06:25:24Z', foo: 'bar' },
{ updated_at: '2012-01-05T04:13:24Z', foo: 'bar' },
{ updated_at: '2012-01-09T11:25:13Z', foo: 'bar' } ]
*/
答案 17 :(得分:0)
您可以使用 Lodash 实用程序库解决此问题(这是一个非常有效的库):
const data = [{
"updated_at": "2012-01-01T06:25:24Z",
"foo": "bar"
},
{
"updated_at": "2012-01-09T11:25:13Z",
"foo": "bar"
},
{
"updated_at": "2012-01-05T04:13:24Z",
"foo": "bar"
}
]
const ordered = _.orderBy(
data,
function(item) {
return item.updated_at;
}
);
console.log(ordered)
<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.15/lodash.min.js"></script>
您可以在此处找到文档:https://lodash.com/docs/4.17.15#orderBy
答案 18 :(得分:0)
我面对着同样的事情,所以我用一个通用的原因来处理这个问题,为此我构建了一个函数:
//example: //array: [{name: 'idan', workerType: '3'}, {name: 'stas', workerType: '5'}, {name: 'kirill', workerType: '2'}] //keyField: 'workerType' // keysArray: ['4', '3', '2', '5', '6']
sortByArrayOfKeys = (array, keyField, keysArray) => {
array.sort((a, b) => {
const aIndex = keysArray.indexOf(a[keyField])
const bIndex = keysArray.indexOf(b[keyField])
if (aIndex < bIndex) return -1;
if (aIndex > bIndex) return 1;
return 0;
})
}