I need to sort array of objects by 2 conditions
sort by value
if names are the same show them next to each other in value order
Example example: https://codesandbox.io/s/relaxed-dhawan-sfryng?file=/src/index.js
I provide a solution for it,it's a bit complexed,you can read the comment I have added
const array = [
{
name: "John",
value: 5
},
{
name: "David",
value: 6
},
{
name: "John",
value: 2
},
{
name: "Michael",
value: 4
}
];
const customSort = (data) => {
// create a new array to make elements have same name together
let newArray = data.reduce((a,v) => {
let obj = a.find(e => e.name === v.name)
if(obj){
obj.datas.push(v)
}else{
a.push({'name':v.name,'datas':[v]})
}
return a
},[])
// sort data in the new array by value
newArray.forEach(e => {
e.datas.sort((a,b) => a.value - b.value)
})
// create a value object with boolean value to avoid add duplicate element
let values = data.reduce((a,v) => {
a[v.value] = false
return a
},{})
let keys = Object.keys(values)
let result = []
for(k of keys){
// if the value has iterated,then skip it
if(values[k]){
continue
}
// find data by value
let arr = newArray.filter(e1 => e1.datas.some(e2 => e2.value == k)).flatMap(e => e.datas)
result.push(...arr)
// mark the value already added
arr.forEach(e => {
values[e.value] = true
})
}
return result
}
console.log(customSort(array))
Hope it helps:
const arr = [
{
name: "John",
value: 5
},
{
name: "David",
value: 6
},
{
name: "John",
value: 2
},
{
name: "Michael",
value: 4
}
];
const groupByItems = [];
// Get index of the item based on name in groupByItems array
const getIndex = (name) => {
let index = -1;
groupByItems.forEach((groupByItem, _index) => {
if(groupByItem.name === name) {
index = _index;
}
});
return index;
}
// Group items by their name
const groupByName = () => {
arr.forEach((item) => {
const name = item.name;
const value = item.value;
let index = getIndex(name);
//Means that the [name] has not added before, so we should add it
if(index === -1) {
groupByItems.push({
name: name,
// Hold all values of the [name]
values: [],
// Hold minValue to sort groupByItems by that
minValue: Infinity
});
index = groupByItems.length - 1;
}
// Add current value to the list of values
groupByItems[index].values.push(value);
// Update minValue
if(groupByItems[index].minValue > value) {
groupByItems[index].minValue = value;
}
});
}
groupByName();
//Sort by minValue and then return final objects
const result = groupByItems.sort((a, b) => a.minValue - b.minValue).flatMap((item) => (
item.values.sort((firstValue, secondValue) => firstValue - secondValue).map((value) => {
return {
name: item.name,
value: value
}
})
));
console.log(result);
Related
I have an Array of objects and one object
const filterArray = [{bestTimeToVisit: 'Before 10am'}, {bestDayToVisit: Monday}]
This values are setting in a reducer and the payload will be like
{bestTimeToVisit: 'After 10am'}
or
{bestDayToVisit: Tuesday}.
So what I need is when I get a payload {bestTimeToVisit: 'After 10am'} and if bestTimeToVisit not in filterList array, then add this value to the filterList array.
And if bestTimeToVisit already in the array with different value, then replace the value of that object with same key
if(filterArray.hasOwnProperty("bestTimeToVisit")) {
filterArray["bestTimeToVisit"] = payload["bestTimeToVisit"];
} else {
filterArray.push({"bestTimeToVisit": payload["bestTimeToVisit"]});
}
I convert the object array into a regular object and then back into an object array. makes things less complicated. I'm making the assumption each object coming back only has one key/value and that order doesnt matter.
const objectArraytoObject = (arr) =>
arr.reduce((acc, item) => {
const key = [Object.keys(item)[0]];
return { ...acc, [key]: item[key] };
}, {});
const newValues = [{ someKey: 'something' }, { bestDayToVisit: 'Tuesday' }];
const filterArray = [
{ bestTimeToVisit: 'Before 10am' },
{ bestDayToVisit: 'Monday' },
];
const newValuesObj = objectArraytoObject(newValues);
const filterObj = objectArraytoObject(filterArray);
const combined = { ...filterObj, ...newValuesObj };
const combinedToArray = Object.keys(combined).map((key) => ({
[key]: combined[key],
}));
console.log(combinedToArray);
Need to iterate over the array and find objects that satisfy for modification or addition if none are found.
function checkReduced(filterrray,valueToCheck="After 10am"){
let isNotFound =true;
for(let timeItem of filterrray) {
if(timeItem.bestTimeToVisit && timeItem.bestTimeToVisit !== valueToCheck) {
timeItem.bestTimeToVisit=valueToCheck;
isNotFound=false;
break;
}
}
if(isNotFound){filterrray.push({bestTimeToVisit:valueToCheck})}
}
const filterArray = [{bestDayToVisit: "Monday"}];
checkReduced(filterArray,"After 9am");//calling the function
const updateOrAdd = (arr, newItem) => {
// get the new item key
const newItemKey = Object.keys(newItem)[0];
// get the object have the same key
const find = arr.find(item => Object.keys(item).includes(newItemKey));
if(find) { // the find object is a reference type
find[newItemKey] = newItem[newItemKey]; // update the value
} else {
arr.push(newItem); // push new item if there is no object have the same key
}
return arr;
}
// tests
updateOrAdd([{ a: 1 }], { b: 2 }) // => [{ a: 1 }, { b: 2 }]
updateOrAdd([{ a: 1 }], { a: 2 }) // => [{ a: 2 }]
I have a source array and target array, based on the target array need to update the source array
sourceAry = [{name:'Label1', value: 'label1', children:[{name:'Ammu'},{name:'Rahual'},{name:'Anu'}]},
{name:'Label2', value: 'label2', children:[{name:'Hari'},{name:'Tom'}]},
];
targetAry = [{name:'Label1', value: 'label1', children:[{name:'Anu'}]},
{name:'Label2', value: 'label2', children:[{name:'Hari'},{name:'Tom'}]},
];
resultAry = [{name:'Label1', value: 'label1', children:[{name:'Ammu'},{name:'Rahual'}]}
]},
];
Code which I try
let resultAry = sourceAry.map((obj) => {
obj.children.map((elem) =>{
targetAry.filter(parent => parent.children.filter((el) => {
el.name !== elem.name}))
})
})
console.log(resultAry, 'NEW', list);
you could start start with some facilities to make it simpler:
const indexBy = (f, data) => data.reduce((acc, x) => Object.assign(acc, { [f(x)]: x }), {})
const remove = (keyFn, dataToRemove, from) => {
const dataToRemoveIndexed = indexBy(keyFn, dataToRemove);
return from.filter(it => !(keyFn(it) in dataToRemoveIndexed));
}
we introduce the indexBy here, to make removal O(m+n), instead of O(m^2) (if there are many items in the collection to check)
then you can use it like this:
const targetIndexed = indexBy(it => it.name, targetAry);
const result = sourceAry.map(
it => ({
...it,
children: remove(
it => it.name,
(targetIndexed[it.name] || {}).children || [],
it.children
)
})
)
so it leaves you with the following result:
[
{"name":"Label1","value":"label1","children":[{"name":"Ammu"}, {"name":"Rahual"}]},
{"name":"Label2","value":"label2","children":[]}
]
if you also want to delete the item with empty children, you can just filter it out: result.filter(it => it.children.length > 0)
Ciao, try something like this:
sourceAry = [{name:'Label1', value: 'label1', children:[{name:'Ammu'},{name:'Rahual'},{name:'Anu'}]}, {name:'Label2', value: 'label2', children:[{name:'Hari'},{name:'Tom'},{name:'Ammu'},{name:'Rahual'},{name:'Anu'}]}, {name:'Label3', value: 'label3', children:[{name:'Ammu'},{name:'Rahual'},{name:'Anu'}]} ];
targetAry = [{name:'Label1', value: 'label1', children:[{name:'Anu'}]},
{name:'Label2', value: 'label2', children:[{name:'Hari'},{name:'Tom'}]},
];
let result = [];
sourceAry.forEach(source => {
let filter = targetAry.filter(target => target.name === source.name)
if (filter.length > 0) {
let filterchildren = source.children.filter(a => !filter[0].children.map(b=>b.name).includes(a.name));
if (filterchildren.length > 0) {
let resultobj = source;
resultobj.children = filterchildren;
result.push(resultobj);
}
}
else result.push(source);
})
console.log(result)
I filter targetAry based on sourceAry name. Then subtract children with .filter(a => !filter[0].children.map(b=>b.name).includes(a.name)); and finally push element found in result array.
I have an array of objects
const data = [{
Description: "confirm"
Id: "1"
Name: "confirm"
Value: "VIP:confirm"
}, {
Description: "validate"
Id: "2"
Name: "validate"
Value: "VIP:validate"
}, {
Description: "Sent"
Id: "2"
Name: "Sent"
Value: "VIP:Sent"
}]
Now, I am trying to get the description by passing the value:
const valuesObject = [
"VIP:Confirmed",
"VIP:Validated",
"VIP:Sent"
]
Now, Values data is like
const getDescription = (
value: string,
Values: Array < >
) => {
let allValues = _.find(Values, item => item.Value === value)
return resolve(allValues)
}
const resolve = (object) => {
return object?.Description ? object.Description : object?.Name ?? ''
}
Now, here I am doing ,
const status = valuesObject.map((value) => {
return getDescription(value, data)
})
return status.join('/')
I was expecting it should return me Confirmed/Validated/Sent
It returns but function gets called multiple times. can any one help me with this ?
Use _.intersectionWith() to get objects with the Value property that matches one of an array of values. Then map to get the Description or Name:
const getDescription = (arr, values) => _.map(
_.intersectionWith(arr, values, (o, v) => o.Value === v), // get all objects with matching values
({ Description, Name = '' }) => Description || Name // map to description / name / empty string
).join('/')
const data = [{"Description":"Confirmed","Id":"1","Name":"confirm","Value":"VIP:Confirmed"},{"Description":"Validated","Id":"2","Name":"validate","Value":"VIP:Validated"},{"Description":"Sent","Id":"2","Name":"Sent","Value":"VIP:Sent"}]
const valuesObject = ["VIP:Confirmed","VIP:Validated","VIP:Sent"]
const result = getDescription(data, valuesObject)
console.log(result)
<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.19/lodash.js"></script>
Using lodash/fp you can generate the getDescription() function with _.flow():
const getDescription = _.flow(
_.intersectionWith((o, v) => o.Value === v), // get all objects with matching values
_.map(({ Description, Name = '' }) => Description || Name), // map to description / name / empty string
_.join('/')
)
const data = [{"Description":"Confirmed","Id":"1","Name":"confirm","Value":"VIP:Confirmed"},{"Description":"Validated","Id":"2","Name":"validate","Value":"VIP:Validated"},{"Description":"Sent","Id":"2","Name":"Sent","Value":"VIP:Sent"}]
const valuesObject = ["VIP:Confirmed","VIP:Validated","VIP:Sent"]
const result = getDescription(data, valuesObject)
console.log(result)
<script src='https://cdn.jsdelivr.net/g/lodash#4(lodash.min.js+lodash.fp.min.js)'></script>
I receive from an ajax call an array of object and some of them are the same, so i want want to push only unique objects in an another array.
receivedArray = [{name:italy, id:67},{name:italy, id:67},{name:france, id:89}]
and i want that :
myArray = [{name:italy, id:67},{name:france, id:89}]
how can i do that ?
Use reduce & findIndex method. findIndex will return the index of the object if the accumulator array already have an object where the id matches. If index is -1 which mean that accumulator array does not have that object.In that case add the array to the accumulator array
let receivedArray = [{
name: 'italy',
id: 67
}, {
name: 'italy',
id: 67
}, {
name: 'france',
id: 89
}]
let myArray = receivedArray.reduce(function(acc, curr) {
let findIndex = acc.findIndex(function(item) {
return item.id === curr.id;
})
if (findIndex === -1) {
acc.push(curr)
}
return acc;
}, [])
console.log(myArray)
You can use filter and Set to do something like this perhaps:
receivedArray = [{name:'italy', id:67},{name:'italy', id:67},{name:'france', id:89}]
mySet = new Set();
myArray = receivedArray.filter(e => {
if (mySet.has(e['id'])) {
return false;
} else {
mySet.add(e['id']);
return true;
}
})
console.log(myArray);
This can be easily solved in es6:
const receivedArray = [{name:'italy', id:67},{name:'italy', id:67},{name:'france', id:89}]
const newArr = receivedArray.filter((item, index, self) =>
index === self.findIndex((i) => (
i.id === item.id && i.name === item.name
))
)
console.log(newArr)
This answer is already close, and there are some answers how to get unique values in an array (remove duplicates,)though I can't make it work for the case where it is about an array of objects, and the property that should be filtered is an array. Sorry, I am a JS newbie. Thanks for the help.
I have an array of objects like this
const posts = [
post1: {
id: 1,
title: 'One',
tags: ['tagA', 'tagB']
},
post2: {
id: 2,
title: 'Two',
tags: ['tagB', 'tagC']
},
post3: {
id: 3,
title: 'Three',
tags: ['tagB', tagC, tagD]
]
What I would need is an array of all unique tags ... in the case above with an expected output like this:
// [tagA, tagB, tagC, tagD]
EDIT / UPDATE
The key in the array of objects is used to manage the state of the react component... e.g.
constructor(props) {
super(props);
this.state = {
posts: []
};
}
...
updatePost = (key, updatedPost) => {
//1. Take copy of the current this.state.
const posts = {...this.state.texts};
//2. Update that state
posts[key] = updatedPost;
//3. Set that to state
const options = { encrypt: false }
putFile(postsFileName, JSON.stringify(posts), options)
.then(() => {
this.setState({
posts: posts
})
})
};
Assuming that the input is on [ {} , {} ] format:
You can use concat and map to flatten your array. Use new Set to get the unique values.
const posts = [{"id":1,"title":"One","tags":["tagA","tagB"]},{"id":2,"title":"Two","tags":["tagB","tagC"]},{"id":3,"title":"Three","tags":["tagB","tagC","tagD"]}];
var result = [...new Set([].concat(...posts.map(o => o.tags)))];
console.log(result);
If the variable is an object ( {a:{} , b:{} } ) , you can use Object.values to convert the object into an array.
const posts = {"post1":{"id":1,"title":"One","tags":["tagA","tagB"]},"post2":{"id":2,"title":"Two","tags":["tagB","tagC"]},"post3":{"id":3,"title":"Three","tags":["tagB","tagC","tagD"]}}
var result = [...new Set([].concat(...Object.values(posts).map(o => o.tags)))];
console.log(result);
You can reduce your posts and iterate over the tags and push those to the result that you haven't encountered already:
const posts = [
{
id: 1,
title: "One",
tags: ["tagA", "tagB"]
},
{
id: 2,
title: "Two",
tags: ["tagB", "tagC"]
},
{
id: 3,
title: "Three",
tags: ["tagB", "tagC", "tagD"]
}
];
const uniqueTags = posts.reduce((result, post) => {
post.tags.forEach(tag => {
if (!result.includes(tag)) {
result.push(tag);
}
});
return result;
}, []);
console.log(uniqueTags);
This is assuming you know that the array key is always 'tags'.
let filter = {};
let result = [];
posts.forEach(post => {
const tags = post['tags'];
tags.forEach(tag => {
if (!filter.hasOwnProperty(tag)) {
result.push(tag);
filter[tag] = true;
}
});
});
with jquery you can do something similar to this (not Tested):
var results = [];
$.each(myObject, function(key,valueObj){
var check.isArray(obj);
if(check){
alert(key + "/" + valueObj );
/*replace repeat*/
var sorted_check = check.slice().sort(); // You can define the comparing function here.
// JS by default uses a crappy string compare.
// (we use slice to clone the array so the
// original array won't be modified)
for (var i = 0; i < sorted_check.length - 1; i++) {
if (sorted_check[i + 1] == sorted_check[i]) {
results.push(sorted_check[i]);
}
}
}
});
and a good way with indexof:
Array.prototype.unique = function() {
var a = [];
for ( i = 0; i < this.length; i++ ) {
var current = this[i];
if (a.indexOf(current) < 0) a.push(current);
}
this.length = 0;
for ( i = 0; i < a.length; i++ ) {
this.push( a[i] );
}
return this;
}
Array.prototype.unique = function() {
var a = [];
for ( i = 0; i < this.length; i++ ) {
var current = this[i];
if (a.indexOf(current) < 0) a.push(current);
}
return a;
}
And Follow UP:
Array.prototype.unique = function(mutate) {
var unique = this.reduce(function(accum, current) {
if (accum.indexOf(current) < 0) {
accum.push(current);
}
return accum;
}, []);
if (mutate) {
this.length = 0;
for (let i = 0; i < unique.length; ++i) {
this.push(unique[i]);
}
return this;
}
return unique;
}
If you want to use a functional library like Ramda.js you can do this:
const posts = [
{
id: 1,
title: 'One',
tags: ['tagA', 'tagB'],
},
{
id: 2,
title: 'Two',
tags: ['tagB', 'tagC'],
},
{
id: 3,
title: 'Three',
tags: ['tagB', 'tagC', 'tagD'],
},
];
var unique = R.uniq(R.flatten(R.map(R.prop('tags'), posts)))
console.log(unique)
<script src="https://cdnjs.cloudflare.com/ajax/libs/ramda/0.25.0/ramda.min.js"></script>