Sort array by child's child
0
The situation is: I have an array of objects, in which every object has an array of objects. The array looks like this:
[
{
"dislikes": [
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511001,
"timezoneOffset": -60,
"year": 118
},
},
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511008,
"timezoneOffset": -60,
"year": 118
},
}
],
},
{
"dislikes": [
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511011,
"timezoneOffset": -60,
"year": 118
},
},
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511028,
"timezoneOffset": -60,
"year": 118
},
}
],
}
]
So I want to sort the users, and the dislikes by the time in their dislikes. So the user with the earliest dislike would be first, as well as the earliest dislike would be first in each users' dislikes array. I believe I have to do multiple sorts, but how can I do that exactly?
javascript arrays sorting
asked Nov 23 '18 at 9:49
Alex Ironside
1,004723
add a comment |
0
The situation is: I have an array of objects, in which every object has an array of objects. The array looks like this:
[
{
"dislikes": [
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511001,
"timezoneOffset": -60,
"year": 118
},
},
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511008,
"timezoneOffset": -60,
"year": 118
},
}
],
},
{
"dislikes": [
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511011,
"timezoneOffset": -60,
"year": 118
},
},
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511028,
"timezoneOffset": -60,
"year": 118
},
}
],
}
]
So I want to sort the users, and the dislikes by the time in their dislikes. So the user with the earliest dislike would be first, as well as the earliest dislike would be first in each users' dislikes array. I believe I have to do multiple sorts, but how can I do that exactly?
javascript arrays sorting
asked Nov 23 '18 at 9:49
Alex Ironside
1,004723
Can you please clarify why you need to break the createDate into elements if the requirement is to sort it?
– Carlos Martins
Nov 23 '18 at 9:59
What do you mean? I want to sort the array of users and dislikes by the time in createdDate. The createdDate object is created with Java and I have no control over it. I just have to sort it.
– Alex Ironside
Nov 23 '18 at 10:01
add a comment |
0
0
0
The situation is: I have an array of objects, in which every object has an array of objects. The array looks like this:
[
{
"dislikes": [
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511001,
"timezoneOffset": -60,
"year": 118
},
},
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511008,
"timezoneOffset": -60,
"year": 118
},
}
],
},
{
"dislikes": [
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511011,
"timezoneOffset": -60,
"year": 118
},
},
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511028,
"timezoneOffset": -60,
"year": 118
},
}
],
}
]
So I want to sort the users, and the dislikes by the time in their dislikes. So the user with the earliest dislike would be first, as well as the earliest dislike would be first in each users' dislikes array. I believe I have to do multiple sorts, but how can I do that exactly?
javascript arrays sorting
asked Nov 23 '18 at 9:49
Alex Ironside
1,004723
The situation is: I have an array of objects, in which every object has an array of objects. The array looks like this:
[
{
"dislikes": [
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511001,
"timezoneOffset": -60,
"year": 118
},
},
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511008,
"timezoneOffset": -60,
"year": 118
},
}
],
},
{
"dislikes": [
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511011,
"timezoneOffset": -60,
"year": 118
},
},
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511028,
"timezoneOffset": -60,
"year": 118
},
}
],
}
]
So I want to sort the users, and the dislikes by the time in their dislikes. So the user with the earliest dislike would be first, as well as the earliest dislike would be first in each users' dislikes array. I believe I have to do multiple sorts, but how can I do that exactly?
javascript arrays sorting
javascript arrays sorting
asked Nov 23 '18 at 9:49
Alex Ironside
1,004723
asked Nov 23 '18 at 9:49
Alex Ironside
1,004723
asked Nov 23 '18 at 9:49
Alex Ironside
1,004723
asked Nov 23 '18 at 9:49
Alex Ironside
1,004723
asked Nov 23 '18 at 9:49
Alex Ironside
1,004723
1,004723
Can you please clarify why you need to break the createDate into elements if the requirement is to sort it?
– Carlos Martins
Nov 23 '18 at 9:59
What do you mean? I want to sort the array of users and dislikes by the time in createdDate. The createdDate object is created with Java and I have no control over it. I just have to sort it.
– Alex Ironside
Nov 23 '18 at 10:01
add a comment |
Can you please clarify why you need to break the createDate into elements if the requirement is to sort it?
– Carlos Martins
Nov 23 '18 at 9:59
What do you mean? I want to sort the array of users and dislikes by the time in createdDate. The createdDate object is created with Java and I have no control over it. I just have to sort it.
– Alex Ironside
Nov 23 '18 at 10:01
Can you please clarify why you need to break the createDate into elements if the requirement is to sort it?
– Carlos Martins
Nov 23 '18 at 9:59
Can you please clarify why you need to break the createDate into elements if the requirement is to sort it?
– Carlos Martins
Nov 23 '18 at 9:59
What do you mean? I want to sort the array of users and dislikes by the time in createdDate. The createdDate object is created with Java and I have no control over it. I just have to sort it.
– Alex Ironside
Nov 23 '18 at 10:01
What do you mean? I want to sort the array of users and dislikes by the time in createdDate. The createdDate object is created with Java and I have no control over it. I just have to sort it.
– Alex Ironside
Nov 23 '18 at 10:01
add a comment |
4 Answers
4
active
oldest
votes
1
Check the code below. This will let you sort based on time:
function sortByTime(obj1, obj2){
return obj1.time - obj2.time;
}
array.sort((obj1, obj2)=>{
obj1.dislikes.sort(sortByTime);
obj2.dislikes.sort(sortByTime);
return obj1.dislikes[0].time - obj2.dislikes[0].time;
});
I did not get what you meant by earliest time. The above code sorts time in ascending order.
NOTE: The above code does not handle edge cases where a property night be missing
answered Nov 23 '18 at 10:02
Royson
3321311
Mutates elements in array and is very inefficient to sort on every compare. Will also crash or bug out when user has no dislikes.
– HMR
Nov 23 '18 at 10:20
add a comment |
2
You can map the items and add a property to it containing the earliest dislike and then sort on that:
const data = [{"dislikes":[{"createDate":{"date":11,"day":0,"hours":18,"minutes":15,"month":10,"seconds":11,"time":1541956511001,"timezoneOffset":-60,"year":118}},{"createDate":{"date":11,"day":0,"hours":18,"minutes":15,"month":10,"seconds":11,"time":1541956511008,"timezoneOffset":-60,"year":118}}]},{"dislikes":[{"createDate":{"date":11,"day":0,"hours":18,"minutes":15,"month":10,"seconds":11,"time":1541956511011,"timezoneOffset":-60,"year":118}},{"createDate":{"date":11,"day":0,"hours":18,"minutes":15,"month":10,"seconds":11,"time":1541956511028,"timezoneOffset":-60,"year":118}}]}];
console.log(
data
//map and add newestDislike property
.map((d) => ({
...d,
//reduce and only takes the lowest time value
newestDislike: (d.dislikes || ).reduce(
(result, item) =>
item.createDate.time < result
? item.createDate.time
: result,
Infinity, //defaults to infinity (if no dislikes)
),
}))
.sort((a, b) => a.newestDislike - b.newestDislike),
);If the dislikes in the user are already sorted by oldest date first then you can skip the map and reduce part. If a user can have empty dislikes or undefined then make sure you use a getter function with a default so your code won't crash:
//gets a nested prop from object or returns defaultValue
const get = (o = {}, path, defaultValue) => {
const recur = (o, path, defaultValue) => {
if (o === undefined) return defaultValue;
if (path.length === 0) return o;
if (!(path[0] in o)) return defaultValue;
return recur(o[path[0]], path.slice(1), defaultValue);
};
return recur(o, path, defaultValue);
};
console.log(
data.sort(
(a, b) =>
get(
a,
['dislikes', 0, 'createDate', 'time'],
Infinity,
) -
get(
b,
['dislikes', 0, 'createDate', 'time'],
Infinity,
),
),
);
answered Nov 23 '18 at 10:01
HMR
13.5k113898
1
Good answer that handles undefined and other checks
– Kruthika C S
Nov 23 '18 at 11:40
add a comment |
2
//Supply the array you've metioned as the argument users to the below method, sortDislikesForAllUsers
let sortDislikesForAllUsers = function(users) {
return users.map(user => {
return {
dislikes: user.dislikes.sort((dislikeA, dislikeB) => ((dislikeA.createDate.time < dislikeB.createDate.time) ? -1 : (dislikeA.createDate.time > dislikeB.createDate.time) ? 1 : 0))
}
})
}
//Supply the array returned in the above method as input to the below method, sortUsers
let sortUsers = function(arrayOfSortedDislikesPerUser) {
return arrayOfSortedDislikesPerUser.sort((userA, userB) => ((userA.dislikes[0].createDate.time < userB.dislikes[0].createDate.time) ? -1 : (userA.dislikes[0].createDate.time > userB.dislikes[0].createDate.time) ? 1 : 0))
}
let arrayOfSortedDislikesPerUser = sortDislikesForAllUsers(users);
let finalSortedArray = sortUsers(arrayOfSortedDislikesPerUser);
console.log(finalSortedArray);
In the below snippet,
sortDislikesForAllUsers This method sorts the dislikes for individual
users
sortUsers This method sorts the users based on the first dislike time
of the sorted dislikes array obtained from the above method
Simple :)
Run the below snippet. You can directly copy paste it in your code!
let users = [{
"dislikes": [
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511001,
"timezoneOffset": -60,
"year": 118
},
},
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511008,
"timezoneOffset": -60,
"year": 118
},
}
],
},
{
"dislikes": [
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511011,
"timezoneOffset": -60,
"year": 118
},
},
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511028,
"timezoneOffset": -60,
"year": 118
},
}
],
}]
let sortDislikesForAllUsers = function(users) {
return users.map(user => {
return {
dislikes: user.dislikes.sort((dislikeA, dislikeB) => ((dislikeA.createDate.time < dislikeB.createDate.time) ? -1 : (dislikeA.createDate.time > dislikeB.createDate.time) ? 1 : 0))
}
})
}
let sortUsers = function(arrayOfSortedDislikesPerUser) {
return arrayOfSortedDislikesPerUser.sort((userA, userB) => ((userA.dislikes[0].createDate.time < userB.dislikes[0].createDate.time) ? -1 : (userA.dislikes[0].createDate.time > userB.dislikes[0].createDate.time) ? 1 : 0))
}
let arrayOfSortedDislikesPerUser = sortDislikesForAllUsers(users);
let finalSortedArray = sortUsers(arrayOfSortedDislikesPerUser);
console.log(finalSortedArray);EDIT: WRT to the comment by @HMR:
1. It mutates the original array. Yes. If you want to avoid mutation, you must create a copy of the sent array.
let noRefCopy = new Array()
noRefCopy = noRefCopy.concat(originalArr)
Now, perform sorting on the copy and return the same.
2. If you wanna have checks for undefined etc, sure you can.
The above answer attempts to address the logic. Sure we can address the above 2 concerns if the question is really specific to them.
Cheers,
Kruthika
answered Nov 23 '18 at 10:49
Kruthika C S
140112
Sort mutates the array so after executingsortDislikesForAllUsersyou've changed the original array (usually not a good thing). What if a user has no dislikes, say dislikes is an empty array or even undefined for a user?
– HMR
Nov 23 '18 at 11:06
Thanks for the comment HMR. The points you mentioned can be effectively addressed. 1. It mutates the original array. Yes. If you want to avoid mutation, you must create a copy of the sent array.let noRefCopy = new Array() noRefCopy = noRefCopy.concat(originalArr)Now, perform sorting on the copy and return the same. 2. If you wanna have checkes for undefined etc, sure you can. The above answer attempts to address the logic. Sure we can address the above 2 concerns. PS:If you say, creating copy is a space concern now, you must create copy if you wanna avoid mutation
– Kruthika C S
Nov 23 '18 at 11:29
user.dislikes.slice().sort(...would fix the mutation as well but a user without dislikes (empty array or undefined) would crash your code. To fix that you will need a getter (see second part of my answer)
– HMR
Nov 23 '18 at 11:35
add a comment |
1
Something like as follows (with lodash.js)
_.each(users, (u) => { u.dislikes = _.sortBy(u.dislikes, 'createdDate.time'); });
users = _.sortBy(users, 'dislikes[0].createdDate.time');
answered Nov 23 '18 at 10:01
Andrey
1164
add a comment |
Your Answer
StackExchange.ifUsing("editor", function () {
StackExchange.using("externalEditor", function () {
StackExchange.using("snippets", function () {
StackExchange.snippets.init();
});
});
}, "code-snippets");
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "1"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
draft saved
draft discarded
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53444228%2fsort-array-by-childs-child%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
4 Answers
4
active
oldest
votes
4 Answers
4
active
oldest
votes
active
oldest
votes
active
oldest
votes
1
Check the code below. This will let you sort based on time:
function sortByTime(obj1, obj2){
return obj1.time - obj2.time;
}
array.sort((obj1, obj2)=>{
obj1.dislikes.sort(sortByTime);
obj2.dislikes.sort(sortByTime);
return obj1.dislikes[0].time - obj2.dislikes[0].time;
});
I did not get what you meant by earliest time. The above code sorts time in ascending order.
NOTE: The above code does not handle edge cases where a property night be missing
answered Nov 23 '18 at 10:02
Royson
3321311
Mutates elements in array and is very inefficient to sort on every compare. Will also crash or bug out when user has no dislikes.
– HMR
Nov 23 '18 at 10:20
add a comment |
1
Check the code below. This will let you sort based on time:
function sortByTime(obj1, obj2){
return obj1.time - obj2.time;
}
array.sort((obj1, obj2)=>{
obj1.dislikes.sort(sortByTime);
obj2.dislikes.sort(sortByTime);
return obj1.dislikes[0].time - obj2.dislikes[0].time;
});
I did not get what you meant by earliest time. The above code sorts time in ascending order.
NOTE: The above code does not handle edge cases where a property night be missing
answered Nov 23 '18 at 10:02
Royson
3321311
Mutates elements in array and is very inefficient to sort on every compare. Will also crash or bug out when user has no dislikes.
– HMR
Nov 23 '18 at 10:20
add a comment |
1
1
1
Check the code below. This will let you sort based on time:
function sortByTime(obj1, obj2){
return obj1.time - obj2.time;
}
array.sort((obj1, obj2)=>{
obj1.dislikes.sort(sortByTime);
obj2.dislikes.sort(sortByTime);
return obj1.dislikes[0].time - obj2.dislikes[0].time;
});
I did not get what you meant by earliest time. The above code sorts time in ascending order.
NOTE: The above code does not handle edge cases where a property night be missing
answered Nov 23 '18 at 10:02
Royson
3321311
Check the code below. This will let you sort based on time:
function sortByTime(obj1, obj2){
return obj1.time - obj2.time;
}
array.sort((obj1, obj2)=>{
obj1.dislikes.sort(sortByTime);
obj2.dislikes.sort(sortByTime);
return obj1.dislikes[0].time - obj2.dislikes[0].time;
});
I did not get what you meant by earliest time. The above code sorts time in ascending order.
NOTE: The above code does not handle edge cases where a property night be missing
answered Nov 23 '18 at 10:02
Royson
3321311
edited Nov 23 '18 at 10:24
answered Nov 23 '18 at 10:02
Royson
3321311
answered Nov 23 '18 at 10:02
Royson
3321311
answered Nov 23 '18 at 10:02
Royson
3321311
3321311
Mutates elements in array and is very inefficient to sort on every compare. Will also crash or bug out when user has no dislikes.
– HMR
Nov 23 '18 at 10:20
add a comment |
Mutates elements in array and is very inefficient to sort on every compare. Will also crash or bug out when user has no dislikes.
– HMR
Nov 23 '18 at 10:20
Mutates elements in array and is very inefficient to sort on every compare. Will also crash or bug out when user has no dislikes.
– HMR
Nov 23 '18 at 10:20
Mutates elements in array and is very inefficient to sort on every compare. Will also crash or bug out when user has no dislikes.
– HMR
Nov 23 '18 at 10:20
add a comment |
2
You can map the items and add a property to it containing the earliest dislike and then sort on that:
const data = [{"dislikes":[{"createDate":{"date":11,"day":0,"hours":18,"minutes":15,"month":10,"seconds":11,"time":1541956511001,"timezoneOffset":-60,"year":118}},{"createDate":{"date":11,"day":0,"hours":18,"minutes":15,"month":10,"seconds":11,"time":1541956511008,"timezoneOffset":-60,"year":118}}]},{"dislikes":[{"createDate":{"date":11,"day":0,"hours":18,"minutes":15,"month":10,"seconds":11,"time":1541956511011,"timezoneOffset":-60,"year":118}},{"createDate":{"date":11,"day":0,"hours":18,"minutes":15,"month":10,"seconds":11,"time":1541956511028,"timezoneOffset":-60,"year":118}}]}];
console.log(
data
//map and add newestDislike property
.map((d) => ({
...d,
//reduce and only takes the lowest time value
newestDislike: (d.dislikes || ).reduce(
(result, item) =>
item.createDate.time < result
? item.createDate.time
: result,
Infinity, //defaults to infinity (if no dislikes)
),
}))
.sort((a, b) => a.newestDislike - b.newestDislike),
);If the dislikes in the user are already sorted by oldest date first then you can skip the map and reduce part. If a user can have empty dislikes or undefined then make sure you use a getter function with a default so your code won't crash:
//gets a nested prop from object or returns defaultValue
const get = (o = {}, path, defaultValue) => {
const recur = (o, path, defaultValue) => {
if (o === undefined) return defaultValue;
if (path.length === 0) return o;
if (!(path[0] in o)) return defaultValue;
return recur(o[path[0]], path.slice(1), defaultValue);
};
return recur(o, path, defaultValue);
};
console.log(
data.sort(
(a, b) =>
get(
a,
['dislikes', 0, 'createDate', 'time'],
Infinity,
) -
get(
b,
['dislikes', 0, 'createDate', 'time'],
Infinity,
),
),
);
answered Nov 23 '18 at 10:01
HMR
13.5k113898
1
Good answer that handles undefined and other checks
– Kruthika C S
Nov 23 '18 at 11:40
add a comment |
2
You can map the items and add a property to it containing the earliest dislike and then sort on that:
const data = [{"dislikes":[{"createDate":{"date":11,"day":0,"hours":18,"minutes":15,"month":10,"seconds":11,"time":1541956511001,"timezoneOffset":-60,"year":118}},{"createDate":{"date":11,"day":0,"hours":18,"minutes":15,"month":10,"seconds":11,"time":1541956511008,"timezoneOffset":-60,"year":118}}]},{"dislikes":[{"createDate":{"date":11,"day":0,"hours":18,"minutes":15,"month":10,"seconds":11,"time":1541956511011,"timezoneOffset":-60,"year":118}},{"createDate":{"date":11,"day":0,"hours":18,"minutes":15,"month":10,"seconds":11,"time":1541956511028,"timezoneOffset":-60,"year":118}}]}];
console.log(
data
//map and add newestDislike property
.map((d) => ({
...d,
//reduce and only takes the lowest time value
newestDislike: (d.dislikes || ).reduce(
(result, item) =>
item.createDate.time < result
? item.createDate.time
: result,
Infinity, //defaults to infinity (if no dislikes)
),
}))
.sort((a, b) => a.newestDislike - b.newestDislike),
);If the dislikes in the user are already sorted by oldest date first then you can skip the map and reduce part. If a user can have empty dislikes or undefined then make sure you use a getter function with a default so your code won't crash:
//gets a nested prop from object or returns defaultValue
const get = (o = {}, path, defaultValue) => {
const recur = (o, path, defaultValue) => {
if (o === undefined) return defaultValue;
if (path.length === 0) return o;
if (!(path[0] in o)) return defaultValue;
return recur(o[path[0]], path.slice(1), defaultValue);
};
return recur(o, path, defaultValue);
};
console.log(
data.sort(
(a, b) =>
get(
a,
['dislikes', 0, 'createDate', 'time'],
Infinity,
) -
get(
b,
['dislikes', 0, 'createDate', 'time'],
Infinity,
),
),
);
answered Nov 23 '18 at 10:01
HMR
13.5k113898
1
Good answer that handles undefined and other checks
– Kruthika C S
Nov 23 '18 at 11:40
add a comment |
2
2
2
You can map the items and add a property to it containing the earliest dislike and then sort on that:
const data = [{"dislikes":[{"createDate":{"date":11,"day":0,"hours":18,"minutes":15,"month":10,"seconds":11,"time":1541956511001,"timezoneOffset":-60,"year":118}},{"createDate":{"date":11,"day":0,"hours":18,"minutes":15,"month":10,"seconds":11,"time":1541956511008,"timezoneOffset":-60,"year":118}}]},{"dislikes":[{"createDate":{"date":11,"day":0,"hours":18,"minutes":15,"month":10,"seconds":11,"time":1541956511011,"timezoneOffset":-60,"year":118}},{"createDate":{"date":11,"day":0,"hours":18,"minutes":15,"month":10,"seconds":11,"time":1541956511028,"timezoneOffset":-60,"year":118}}]}];
console.log(
data
//map and add newestDislike property
.map((d) => ({
...d,
//reduce and only takes the lowest time value
newestDislike: (d.dislikes || ).reduce(
(result, item) =>
item.createDate.time < result
? item.createDate.time
: result,
Infinity, //defaults to infinity (if no dislikes)
),
}))
.sort((a, b) => a.newestDislike - b.newestDislike),
);If the dislikes in the user are already sorted by oldest date first then you can skip the map and reduce part. If a user can have empty dislikes or undefined then make sure you use a getter function with a default so your code won't crash:
//gets a nested prop from object or returns defaultValue
const get = (o = {}, path, defaultValue) => {
const recur = (o, path, defaultValue) => {
if (o === undefined) return defaultValue;
if (path.length === 0) return o;
if (!(path[0] in o)) return defaultValue;
return recur(o[path[0]], path.slice(1), defaultValue);
};
return recur(o, path, defaultValue);
};
console.log(
data.sort(
(a, b) =>
get(
a,
['dislikes', 0, 'createDate', 'time'],
Infinity,
) -
get(
b,
['dislikes', 0, 'createDate', 'time'],
Infinity,
),
),
);
answered Nov 23 '18 at 10:01
HMR
13.5k113898
You can map the items and add a property to it containing the earliest dislike and then sort on that:
const data = [{"dislikes":[{"createDate":{"date":11,"day":0,"hours":18,"minutes":15,"month":10,"seconds":11,"time":1541956511001,"timezoneOffset":-60,"year":118}},{"createDate":{"date":11,"day":0,"hours":18,"minutes":15,"month":10,"seconds":11,"time":1541956511008,"timezoneOffset":-60,"year":118}}]},{"dislikes":[{"createDate":{"date":11,"day":0,"hours":18,"minutes":15,"month":10,"seconds":11,"time":1541956511011,"timezoneOffset":-60,"year":118}},{"createDate":{"date":11,"day":0,"hours":18,"minutes":15,"month":10,"seconds":11,"time":1541956511028,"timezoneOffset":-60,"year":118}}]}];
console.log(
data
//map and add newestDislike property
.map((d) => ({
...d,
//reduce and only takes the lowest time value
newestDislike: (d.dislikes || ).reduce(
(result, item) =>
item.createDate.time < result
? item.createDate.time
: result,
Infinity, //defaults to infinity (if no dislikes)
),
}))
.sort((a, b) => a.newestDislike - b.newestDislike),
);If the dislikes in the user are already sorted by oldest date first then you can skip the map and reduce part. If a user can have empty dislikes or undefined then make sure you use a getter function with a default so your code won't crash:
//gets a nested prop from object or returns defaultValue
const get = (o = {}, path, defaultValue) => {
const recur = (o, path, defaultValue) => {
if (o === undefined) return defaultValue;
if (path.length === 0) return o;
if (!(path[0] in o)) return defaultValue;
return recur(o[path[0]], path.slice(1), defaultValue);
};
return recur(o, path, defaultValue);
};
console.log(
data.sort(
(a, b) =>
get(
a,
['dislikes', 0, 'createDate', 'time'],
Infinity,
) -
get(
b,
['dislikes', 0, 'createDate', 'time'],
Infinity,
),
),
);
const data = [{"dislikes":[{"createDate":{"date":11,"day":0,"hours":18,"minutes":15,"month":10,"seconds":11,"time":1541956511001,"timezoneOffset":-60,"year":118}},{"createDate":{"date":11,"day":0,"hours":18,"minutes":15,"month":10,"seconds":11,"time":1541956511008,"timezoneOffset":-60,"year":118}}]},{"dislikes":[{"createDate":{"date":11,"day":0,"hours":18,"minutes":15,"month":10,"seconds":11,"time":1541956511011,"timezoneOffset":-60,"year":118}},{"createDate":{"date":11,"day":0,"hours":18,"minutes":15,"month":10,"seconds":11,"time":1541956511028,"timezoneOffset":-60,"year":118}}]}];
console.log(
data
//map and add newestDislike property
.map((d) => ({
...d,
//reduce and only takes the lowest time value
newestDislike: (d.dislikes || ).reduce(
(result, item) =>
item.createDate.time < result
? item.createDate.time
: result,
Infinity, //defaults to infinity (if no dislikes)
),
}))
.sort((a, b) => a.newestDislike - b.newestDislike),
);const data = [{"dislikes":[{"createDate":{"date":11,"day":0,"hours":18,"minutes":15,"month":10,"seconds":11,"time":1541956511001,"timezoneOffset":-60,"year":118}},{"createDate":{"date":11,"day":0,"hours":18,"minutes":15,"month":10,"seconds":11,"time":1541956511008,"timezoneOffset":-60,"year":118}}]},{"dislikes":[{"createDate":{"date":11,"day":0,"hours":18,"minutes":15,"month":10,"seconds":11,"time":1541956511011,"timezoneOffset":-60,"year":118}},{"createDate":{"date":11,"day":0,"hours":18,"minutes":15,"month":10,"seconds":11,"time":1541956511028,"timezoneOffset":-60,"year":118}}]}];
console.log(
data
//map and add newestDislike property
.map((d) => ({
...d,
//reduce and only takes the lowest time value
newestDislike: (d.dislikes || ).reduce(
(result, item) =>
item.createDate.time < result
? item.createDate.time
: result,
Infinity, //defaults to infinity (if no dislikes)
),
}))
.sort((a, b) => a.newestDislike - b.newestDislike),
);answered Nov 23 '18 at 10:01
HMR
13.5k113898
edited Nov 23 '18 at 10:24
answered Nov 23 '18 at 10:01
HMR
13.5k113898
answered Nov 23 '18 at 10:01
HMR
13.5k113898
answered Nov 23 '18 at 10:01
HMR
13.5k113898
13.5k113898
1
Good answer that handles undefined and other checks
– Kruthika C S
Nov 23 '18 at 11:40
add a comment |
1
Good answer that handles undefined and other checks
– Kruthika C S
Nov 23 '18 at 11:40
1
1
Good answer that handles undefined and other checks
– Kruthika C S
Nov 23 '18 at 11:40
Good answer that handles undefined and other checks
– Kruthika C S
Nov 23 '18 at 11:40
add a comment |
2
//Supply the array you've metioned as the argument users to the below method, sortDislikesForAllUsers
let sortDislikesForAllUsers = function(users) {
return users.map(user => {
return {
dislikes: user.dislikes.sort((dislikeA, dislikeB) => ((dislikeA.createDate.time < dislikeB.createDate.time) ? -1 : (dislikeA.createDate.time > dislikeB.createDate.time) ? 1 : 0))
}
})
}
//Supply the array returned in the above method as input to the below method, sortUsers
let sortUsers = function(arrayOfSortedDislikesPerUser) {
return arrayOfSortedDislikesPerUser.sort((userA, userB) => ((userA.dislikes[0].createDate.time < userB.dislikes[0].createDate.time) ? -1 : (userA.dislikes[0].createDate.time > userB.dislikes[0].createDate.time) ? 1 : 0))
}
let arrayOfSortedDislikesPerUser = sortDislikesForAllUsers(users);
let finalSortedArray = sortUsers(arrayOfSortedDislikesPerUser);
console.log(finalSortedArray);
In the below snippet,
sortDislikesForAllUsers This method sorts the dislikes for individual
users
sortUsers This method sorts the users based on the first dislike time
of the sorted dislikes array obtained from the above method
Simple :)
Run the below snippet. You can directly copy paste it in your code!
let users = [{
"dislikes": [
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511001,
"timezoneOffset": -60,
"year": 118
},
},
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511008,
"timezoneOffset": -60,
"year": 118
},
}
],
},
{
"dislikes": [
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511011,
"timezoneOffset": -60,
"year": 118
},
},
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511028,
"timezoneOffset": -60,
"year": 118
},
}
],
}]
let sortDislikesForAllUsers = function(users) {
return users.map(user => {
return {
dislikes: user.dislikes.sort((dislikeA, dislikeB) => ((dislikeA.createDate.time < dislikeB.createDate.time) ? -1 : (dislikeA.createDate.time > dislikeB.createDate.time) ? 1 : 0))
}
})
}
let sortUsers = function(arrayOfSortedDislikesPerUser) {
return arrayOfSortedDislikesPerUser.sort((userA, userB) => ((userA.dislikes[0].createDate.time < userB.dislikes[0].createDate.time) ? -1 : (userA.dislikes[0].createDate.time > userB.dislikes[0].createDate.time) ? 1 : 0))
}
let arrayOfSortedDislikesPerUser = sortDislikesForAllUsers(users);
let finalSortedArray = sortUsers(arrayOfSortedDislikesPerUser);
console.log(finalSortedArray);EDIT: WRT to the comment by @HMR:
1. It mutates the original array. Yes. If you want to avoid mutation, you must create a copy of the sent array.
let noRefCopy = new Array()
noRefCopy = noRefCopy.concat(originalArr)
Now, perform sorting on the copy and return the same.
2. If you wanna have checks for undefined etc, sure you can.
The above answer attempts to address the logic. Sure we can address the above 2 concerns if the question is really specific to them.
Cheers,
Kruthika
answered Nov 23 '18 at 10:49
Kruthika C S
140112
Sort mutates the array so after executingsortDislikesForAllUsersyou've changed the original array (usually not a good thing). What if a user has no dislikes, say dislikes is an empty array or even undefined for a user?
– HMR
Nov 23 '18 at 11:06
Thanks for the comment HMR. The points you mentioned can be effectively addressed. 1. It mutates the original array. Yes. If you want to avoid mutation, you must create a copy of the sent array.let noRefCopy = new Array() noRefCopy = noRefCopy.concat(originalArr)Now, perform sorting on the copy and return the same. 2. If you wanna have checkes for undefined etc, sure you can. The above answer attempts to address the logic. Sure we can address the above 2 concerns. PS:If you say, creating copy is a space concern now, you must create copy if you wanna avoid mutation
– Kruthika C S
Nov 23 '18 at 11:29
user.dislikes.slice().sort(...would fix the mutation as well but a user without dislikes (empty array or undefined) would crash your code. To fix that you will need a getter (see second part of my answer)
– HMR
Nov 23 '18 at 11:35
add a comment |
2
//Supply the array you've metioned as the argument users to the below method, sortDislikesForAllUsers
let sortDislikesForAllUsers = function(users) {
return users.map(user => {
return {
dislikes: user.dislikes.sort((dislikeA, dislikeB) => ((dislikeA.createDate.time < dislikeB.createDate.time) ? -1 : (dislikeA.createDate.time > dislikeB.createDate.time) ? 1 : 0))
}
})
}
//Supply the array returned in the above method as input to the below method, sortUsers
let sortUsers = function(arrayOfSortedDislikesPerUser) {
return arrayOfSortedDislikesPerUser.sort((userA, userB) => ((userA.dislikes[0].createDate.time < userB.dislikes[0].createDate.time) ? -1 : (userA.dislikes[0].createDate.time > userB.dislikes[0].createDate.time) ? 1 : 0))
}
let arrayOfSortedDislikesPerUser = sortDislikesForAllUsers(users);
let finalSortedArray = sortUsers(arrayOfSortedDislikesPerUser);
console.log(finalSortedArray);
In the below snippet,
sortDislikesForAllUsers This method sorts the dislikes for individual
users
sortUsers This method sorts the users based on the first dislike time
of the sorted dislikes array obtained from the above method
Simple :)
Run the below snippet. You can directly copy paste it in your code!
let users = [{
"dislikes": [
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511001,
"timezoneOffset": -60,
"year": 118
},
},
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511008,
"timezoneOffset": -60,
"year": 118
},
}
],
},
{
"dislikes": [
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511011,
"timezoneOffset": -60,
"year": 118
},
},
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511028,
"timezoneOffset": -60,
"year": 118
},
}
],
}]
let sortDislikesForAllUsers = function(users) {
return users.map(user => {
return {
dislikes: user.dislikes.sort((dislikeA, dislikeB) => ((dislikeA.createDate.time < dislikeB.createDate.time) ? -1 : (dislikeA.createDate.time > dislikeB.createDate.time) ? 1 : 0))
}
})
}
let sortUsers = function(arrayOfSortedDislikesPerUser) {
return arrayOfSortedDislikesPerUser.sort((userA, userB) => ((userA.dislikes[0].createDate.time < userB.dislikes[0].createDate.time) ? -1 : (userA.dislikes[0].createDate.time > userB.dislikes[0].createDate.time) ? 1 : 0))
}
let arrayOfSortedDislikesPerUser = sortDislikesForAllUsers(users);
let finalSortedArray = sortUsers(arrayOfSortedDislikesPerUser);
console.log(finalSortedArray);EDIT: WRT to the comment by @HMR:
1. It mutates the original array. Yes. If you want to avoid mutation, you must create a copy of the sent array.
let noRefCopy = new Array()
noRefCopy = noRefCopy.concat(originalArr)
Now, perform sorting on the copy and return the same.
2. If you wanna have checks for undefined etc, sure you can.
The above answer attempts to address the logic. Sure we can address the above 2 concerns if the question is really specific to them.
Cheers,
Kruthika
answered Nov 23 '18 at 10:49
Kruthika C S
140112
Sort mutates the array so after executingsortDislikesForAllUsersyou've changed the original array (usually not a good thing). What if a user has no dislikes, say dislikes is an empty array or even undefined for a user?
– HMR
Nov 23 '18 at 11:06
Thanks for the comment HMR. The points you mentioned can be effectively addressed. 1. It mutates the original array. Yes. If you want to avoid mutation, you must create a copy of the sent array.let noRefCopy = new Array() noRefCopy = noRefCopy.concat(originalArr)Now, perform sorting on the copy and return the same. 2. If you wanna have checkes for undefined etc, sure you can. The above answer attempts to address the logic. Sure we can address the above 2 concerns. PS:If you say, creating copy is a space concern now, you must create copy if you wanna avoid mutation
– Kruthika C S
Nov 23 '18 at 11:29
user.dislikes.slice().sort(...would fix the mutation as well but a user without dislikes (empty array or undefined) would crash your code. To fix that you will need a getter (see second part of my answer)
– HMR
Nov 23 '18 at 11:35
add a comment |
2
2
2
//Supply the array you've metioned as the argument users to the below method, sortDislikesForAllUsers
let sortDislikesForAllUsers = function(users) {
return users.map(user => {
return {
dislikes: user.dislikes.sort((dislikeA, dislikeB) => ((dislikeA.createDate.time < dislikeB.createDate.time) ? -1 : (dislikeA.createDate.time > dislikeB.createDate.time) ? 1 : 0))
}
})
}
//Supply the array returned in the above method as input to the below method, sortUsers
let sortUsers = function(arrayOfSortedDislikesPerUser) {
return arrayOfSortedDislikesPerUser.sort((userA, userB) => ((userA.dislikes[0].createDate.time < userB.dislikes[0].createDate.time) ? -1 : (userA.dislikes[0].createDate.time > userB.dislikes[0].createDate.time) ? 1 : 0))
}
let arrayOfSortedDislikesPerUser = sortDislikesForAllUsers(users);
let finalSortedArray = sortUsers(arrayOfSortedDislikesPerUser);
console.log(finalSortedArray);
In the below snippet,
sortDislikesForAllUsers This method sorts the dislikes for individual
users
sortUsers This method sorts the users based on the first dislike time
of the sorted dislikes array obtained from the above method
Simple :)
Run the below snippet. You can directly copy paste it in your code!
let users = [{
"dislikes": [
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511001,
"timezoneOffset": -60,
"year": 118
},
},
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511008,
"timezoneOffset": -60,
"year": 118
},
}
],
},
{
"dislikes": [
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511011,
"timezoneOffset": -60,
"year": 118
},
},
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511028,
"timezoneOffset": -60,
"year": 118
},
}
],
}]
let sortDislikesForAllUsers = function(users) {
return users.map(user => {
return {
dislikes: user.dislikes.sort((dislikeA, dislikeB) => ((dislikeA.createDate.time < dislikeB.createDate.time) ? -1 : (dislikeA.createDate.time > dislikeB.createDate.time) ? 1 : 0))
}
})
}
let sortUsers = function(arrayOfSortedDislikesPerUser) {
return arrayOfSortedDislikesPerUser.sort((userA, userB) => ((userA.dislikes[0].createDate.time < userB.dislikes[0].createDate.time) ? -1 : (userA.dislikes[0].createDate.time > userB.dislikes[0].createDate.time) ? 1 : 0))
}
let arrayOfSortedDislikesPerUser = sortDislikesForAllUsers(users);
let finalSortedArray = sortUsers(arrayOfSortedDislikesPerUser);
console.log(finalSortedArray);EDIT: WRT to the comment by @HMR:
1. It mutates the original array. Yes. If you want to avoid mutation, you must create a copy of the sent array.
let noRefCopy = new Array()
noRefCopy = noRefCopy.concat(originalArr)
Now, perform sorting on the copy and return the same.
2. If you wanna have checks for undefined etc, sure you can.
The above answer attempts to address the logic. Sure we can address the above 2 concerns if the question is really specific to them.
Cheers,
Kruthika
answered Nov 23 '18 at 10:49
Kruthika C S
140112
//Supply the array you've metioned as the argument users to the below method, sortDislikesForAllUsers
let sortDislikesForAllUsers = function(users) {
return users.map(user => {
return {
dislikes: user.dislikes.sort((dislikeA, dislikeB) => ((dislikeA.createDate.time < dislikeB.createDate.time) ? -1 : (dislikeA.createDate.time > dislikeB.createDate.time) ? 1 : 0))
}
})
}
//Supply the array returned in the above method as input to the below method, sortUsers
let sortUsers = function(arrayOfSortedDislikesPerUser) {
return arrayOfSortedDislikesPerUser.sort((userA, userB) => ((userA.dislikes[0].createDate.time < userB.dislikes[0].createDate.time) ? -1 : (userA.dislikes[0].createDate.time > userB.dislikes[0].createDate.time) ? 1 : 0))
}
let arrayOfSortedDislikesPerUser = sortDislikesForAllUsers(users);
let finalSortedArray = sortUsers(arrayOfSortedDislikesPerUser);
console.log(finalSortedArray);
In the below snippet,
sortDislikesForAllUsers This method sorts the dislikes for individual
users
sortUsers This method sorts the users based on the first dislike time
of the sorted dislikes array obtained from the above method
Simple :)
Run the below snippet. You can directly copy paste it in your code!
let users = [{
"dislikes": [
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511001,
"timezoneOffset": -60,
"year": 118
},
},
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511008,
"timezoneOffset": -60,
"year": 118
},
}
],
},
{
"dislikes": [
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511011,
"timezoneOffset": -60,
"year": 118
},
},
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511028,
"timezoneOffset": -60,
"year": 118
},
}
],
}]
let sortDislikesForAllUsers = function(users) {
return users.map(user => {
return {
dislikes: user.dislikes.sort((dislikeA, dislikeB) => ((dislikeA.createDate.time < dislikeB.createDate.time) ? -1 : (dislikeA.createDate.time > dislikeB.createDate.time) ? 1 : 0))
}
})
}
let sortUsers = function(arrayOfSortedDislikesPerUser) {
return arrayOfSortedDislikesPerUser.sort((userA, userB) => ((userA.dislikes[0].createDate.time < userB.dislikes[0].createDate.time) ? -1 : (userA.dislikes[0].createDate.time > userB.dislikes[0].createDate.time) ? 1 : 0))
}
let arrayOfSortedDislikesPerUser = sortDislikesForAllUsers(users);
let finalSortedArray = sortUsers(arrayOfSortedDislikesPerUser);
console.log(finalSortedArray);EDIT: WRT to the comment by @HMR:
1. It mutates the original array. Yes. If you want to avoid mutation, you must create a copy of the sent array.
let noRefCopy = new Array()
noRefCopy = noRefCopy.concat(originalArr)
Now, perform sorting on the copy and return the same.
2. If you wanna have checks for undefined etc, sure you can.
The above answer attempts to address the logic. Sure we can address the above 2 concerns if the question is really specific to them.
Cheers,
Kruthika
let users = [{
"dislikes": [
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511001,
"timezoneOffset": -60,
"year": 118
},
},
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511008,
"timezoneOffset": -60,
"year": 118
},
}
],
},
{
"dislikes": [
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511011,
"timezoneOffset": -60,
"year": 118
},
},
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511028,
"timezoneOffset": -60,
"year": 118
},
}
],
}]
let sortDislikesForAllUsers = function(users) {
return users.map(user => {
return {
dislikes: user.dislikes.sort((dislikeA, dislikeB) => ((dislikeA.createDate.time < dislikeB.createDate.time) ? -1 : (dislikeA.createDate.time > dislikeB.createDate.time) ? 1 : 0))
}
})
}
let sortUsers = function(arrayOfSortedDislikesPerUser) {
return arrayOfSortedDislikesPerUser.sort((userA, userB) => ((userA.dislikes[0].createDate.time < userB.dislikes[0].createDate.time) ? -1 : (userA.dislikes[0].createDate.time > userB.dislikes[0].createDate.time) ? 1 : 0))
}
let arrayOfSortedDislikesPerUser = sortDislikesForAllUsers(users);
let finalSortedArray = sortUsers(arrayOfSortedDislikesPerUser);
console.log(finalSortedArray); let users = [{
"dislikes": [
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511001,
"timezoneOffset": -60,
"year": 118
},
},
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511008,
"timezoneOffset": -60,
"year": 118
},
}
],
},
{
"dislikes": [
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511011,
"timezoneOffset": -60,
"year": 118
},
},
{
"createDate": {
"date": 11,
"day": 0,
"hours": 18,
"minutes": 15,
"month": 10,
"seconds": 11,
"time": 1541956511028,
"timezoneOffset": -60,
"year": 118
},
}
],
}]
let sortDislikesForAllUsers = function(users) {
return users.map(user => {
return {
dislikes: user.dislikes.sort((dislikeA, dislikeB) => ((dislikeA.createDate.time < dislikeB.createDate.time) ? -1 : (dislikeA.createDate.time > dislikeB.createDate.time) ? 1 : 0))
}
})
}
let sortUsers = function(arrayOfSortedDislikesPerUser) {
return arrayOfSortedDislikesPerUser.sort((userA, userB) => ((userA.dislikes[0].createDate.time < userB.dislikes[0].createDate.time) ? -1 : (userA.dislikes[0].createDate.time > userB.dislikes[0].createDate.time) ? 1 : 0))
}
let arrayOfSortedDislikesPerUser = sortDislikesForAllUsers(users);
let finalSortedArray = sortUsers(arrayOfSortedDislikesPerUser);
console.log(finalSortedArray);answered Nov 23 '18 at 10:49
Kruthika C S
140112
edited Nov 23 '18 at 11:44
answered Nov 23 '18 at 10:49
Kruthika C S
140112
answered Nov 23 '18 at 10:49
Kruthika C S
140112
answered Nov 23 '18 at 10:49
Kruthika C S
140112
140112
Sort mutates the array so after executingsortDislikesForAllUsersyou've changed the original array (usually not a good thing). What if a user has no dislikes, say dislikes is an empty array or even undefined for a user?
– HMR
Nov 23 '18 at 11:06
Thanks for the comment HMR. The points you mentioned can be effectively addressed. 1. It mutates the original array. Yes. If you want to avoid mutation, you must create a copy of the sent array.let noRefCopy = new Array() noRefCopy = noRefCopy.concat(originalArr)Now, perform sorting on the copy and return the same. 2. If you wanna have checkes for undefined etc, sure you can. The above answer attempts to address the logic. Sure we can address the above 2 concerns. PS:If you say, creating copy is a space concern now, you must create copy if you wanna avoid mutation
– Kruthika C S
Nov 23 '18 at 11:29
user.dislikes.slice().sort(...would fix the mutation as well but a user without dislikes (empty array or undefined) would crash your code. To fix that you will need a getter (see second part of my answer)
– HMR
Nov 23 '18 at 11:35
add a comment |
Sort mutates the array so after executingsortDislikesForAllUsersyou've changed the original array (usually not a good thing). What if a user has no dislikes, say dislikes is an empty array or even undefined for a user?
– HMR
Nov 23 '18 at 11:06
Thanks for the comment HMR. The points you mentioned can be effectively addressed. 1. It mutates the original array. Yes. If you want to avoid mutation, you must create a copy of the sent array.let noRefCopy = new Array() noRefCopy = noRefCopy.concat(originalArr)Now, perform sorting on the copy and return the same. 2. If you wanna have checkes for undefined etc, sure you can. The above answer attempts to address the logic. Sure we can address the above 2 concerns. PS:If you say, creating copy is a space concern now, you must create copy if you wanna avoid mutation
– Kruthika C S
Nov 23 '18 at 11:29
user.dislikes.slice().sort(...would fix the mutation as well but a user without dislikes (empty array or undefined) would crash your code. To fix that you will need a getter (see second part of my answer)
– HMR
Nov 23 '18 at 11:35
Sort mutates the array so after executing
sortDislikesForAllUsers you've changed the original array (usually not a good thing). What if a user has no dislikes, say dislikes is an empty array or even undefined for a user?– HMR
Nov 23 '18 at 11:06
Sort mutates the array so after executing
sortDislikesForAllUsers you've changed the original array (usually not a good thing). What if a user has no dislikes, say dislikes is an empty array or even undefined for a user?– HMR
Nov 23 '18 at 11:06
Thanks for the comment HMR. The points you mentioned can be effectively addressed. 1. It mutates the original array. Yes. If you want to avoid mutation, you must create a copy of the sent array.
let noRefCopy = new Array() noRefCopy = noRefCopy.concat(originalArr) Now, perform sorting on the copy and return the same. 2. If you wanna have checkes for undefined etc, sure you can. The above answer attempts to address the logic. Sure we can address the above 2 concerns. PS:If you say, creating copy is a space concern now, you must create copy if you wanna avoid mutation– Kruthika C S
Nov 23 '18 at 11:29
Thanks for the comment HMR. The points you mentioned can be effectively addressed. 1. It mutates the original array. Yes. If you want to avoid mutation, you must create a copy of the sent array.
let noRefCopy = new Array() noRefCopy = noRefCopy.concat(originalArr) Now, perform sorting on the copy and return the same. 2. If you wanna have checkes for undefined etc, sure you can. The above answer attempts to address the logic. Sure we can address the above 2 concerns. PS:If you say, creating copy is a space concern now, you must create copy if you wanna avoid mutation– Kruthika C S
Nov 23 '18 at 11:29
user.dislikes.slice().sort(... would fix the mutation as well but a user without dislikes (empty array or undefined) would crash your code. To fix that you will need a getter (see second part of my answer)– HMR
Nov 23 '18 at 11:35
user.dislikes.slice().sort(... would fix the mutation as well but a user without dislikes (empty array or undefined) would crash your code. To fix that you will need a getter (see second part of my answer)– HMR
Nov 23 '18 at 11:35
add a comment |
1
Something like as follows (with lodash.js)
_.each(users, (u) => { u.dislikes = _.sortBy(u.dislikes, 'createdDate.time'); });
users = _.sortBy(users, 'dislikes[0].createdDate.time');
answered Nov 23 '18 at 10:01
Andrey
1164
add a comment |
1
Something like as follows (with lodash.js)
_.each(users, (u) => { u.dislikes = _.sortBy(u.dislikes, 'createdDate.time'); });
users = _.sortBy(users, 'dislikes[0].createdDate.time');
answered Nov 23 '18 at 10:01
Andrey
1164
add a comment |
1
1
1
Something like as follows (with lodash.js)
_.each(users, (u) => { u.dislikes = _.sortBy(u.dislikes, 'createdDate.time'); });
users = _.sortBy(users, 'dislikes[0].createdDate.time');
answered Nov 23 '18 at 10:01
Andrey
1164
Something like as follows (with lodash.js)
_.each(users, (u) => { u.dislikes = _.sortBy(u.dislikes, 'createdDate.time'); });
users = _.sortBy(users, 'dislikes[0].createdDate.time');
answered Nov 23 '18 at 10:01
Andrey
1164
answered Nov 23 '18 at 10:01
Andrey
1164
answered Nov 23 '18 at 10:01
Andrey
1164
answered Nov 23 '18 at 10:01
Andrey
1164
1164
add a comment |
add a comment |
draft saved
draft discarded
Thanks for contributing an answer to Stack Overflow!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
Some of your past answers have not been well-received, and you're in danger of being blocked from answering.
Please pay close attention to the following guidance:
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
draft saved
draft discarded
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53444228%2fsort-array-by-childs-child%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Can you please clarify why you need to break the createDate into elements if the requirement is to sort it?
– Carlos Martins
Nov 23 '18 at 9:59
What do you mean? I want to sort the array of users and dislikes by the time in createdDate. The createdDate object is created with Java and I have no control over it. I just have to sort it.
– Alex Ironside
Nov 23 '18 at 10:01