We Keep Coding

Merge Objects in a array and increase count

[{name:"abc",value:5},{name:"abc",value:10},{name:"abc1",value:5},{name:"abc1",value:15}]
I want to merge it by name so that the new array will be
[{name:"abc",value:15},{name:"abc1",value:20}]
Can i do it with es6 or a simple function

Using reduce and without find or findIndex
const data = [{name:"abc",value:5},{name:"abc",value:10},{name:"abc1",value:5},{name:"abc1",value:15}];
const summedDataObj = data.reduce((acc, entry) => {
if (acc[entry.name]) acc[entry.name].value += entry.value;
else acc[entry.name] = entry;
return acc;
}, {});
const summedDataArr = Object.values(summedDataObj);
console.log(summedDataArr);

We can do it via Array.reduce()
let data = [{name:"abc",value:5},{name:"abc",value:10},{name:"abc1",value:5},{name:"abc1",value:15}]
let result = data.reduce((a,{name,value}) => {
let obj = a.find(e => e.name === name)
if(obj){
obj.value += value
}else{
a.push({name,value})
}
return a
},[])
console.log(result)

you can group the data by name using this function:
function groupBy(arr, prop) {
const map = new Map(Array.from(arr, obj => [obj[prop], []]));
arr.forEach(obj => map.get(obj[prop]).push(obj));
return Array.from(map.values());
}
this yields this result:
[
[
{"name": "abc", "value": 5},
{"name": "abc", "value": 10}
],
[
{"name": "abc1", "value": 5},
{"name": "abc1", "value": 15}
]
]
which can be aggregated by using reduce on each resulting array:
groupedData.map(entry=>entry.reduce((acc,cur)=>({
...acc,
value: acc.value + cur.value
})))
so all together we get:
function groupBy(arr, prop) {
const map = new Map(Array.from(arr, obj => [obj[prop], []]));
arr.forEach(obj => map.get(obj[prop]).push(obj));
return Array.from(map.values());
}
const data = [{name:"abc",value:5},{name:"abc",value:10},{name:"abc1",value:5},{name:"abc1",value:15}]
const aggregatedData = groupBy(data,"name")
.map(entry=>entry.reduce((acc,cur)=>({
...acc,
value:acc.value+cur.value
})))

const obj = [{name:"abc",value:5},{name:"abc",value:10},{name:"abc1",value:5},{name:"abc1",value:15}]
arr = obj.reduce((obj, item) => {
let find = obj.find(i => i.name === item.name && i.date === item.date);
let _d = {
...item
}
find ? (find.value += item.value ) : obj.push(_d);
return obj;
}, [])
console.log(arr);

const data = [{
name: "abc",
value: 5
},
{
name: "abc",
value: 10
},
{
name: "abc1",
value: 5
},
{
name: "abc1",
value: 15
},
];
const groupArr = data.reduce((r, a) => {
const idx = r.findIndex((el) => el.name === a.name);
idx === -1 ? r.push(a) : (r[idx].value += a.value);
return r;
}, []);
console.log(groupArr);

You can achieve this with the help of Array#reduce method.
Live Demo :
const arr = [{name:"abc",value:5},{name:"abc",value:10},{name:"abc1",value:5},{name:"abc1",value:15}];
const res = arr.reduce((obj, curr) => {
if (obj.hasOwnProperty(curr.name) && obj[curr.name].name === curr.name) {
obj[curr.name].value += curr.value
} else {
obj[curr.name] = curr;
}
return obj
}, {});
console.log(Object.values(res));

Json Array compare with different length in javascript

Below code which I am using for creating the new array if the id is the same in arr1 and arr2. But doesn't work since arr1 and arr2 are different. array 1 has index and arr2 is without index. screenshot for your reference. Can someone help?
Note: ID in arr1 is the same as EmpId in arr2
for(let i=0; i<arr1.length; i++) {
merged.push({
...arr1[i],
...(arr2.find((itmInner) => itmInner.id === arr1[i].id))}
);
}
console.log(merged);
Array1 looks like this :
[{"Active":1,"Id":1},
{"Active":1,"Id":3},
{"Active":1,"Id":2}]
Array2 looks something like this:
Below is the sample code on how I am framing array 2:
renderElement(activity){
var arr2 = [] ;
for(var i = 0; i < activity.length; i++) {
obj = activity[i];
if(obj.Id == 28){
fetch(geturl)
.then(function (response) {
return response.json();
})
.then(function (data) {
res = data;
arr2.push(res)
})
}
else{
// Do nothing
}
}
return arr2
}
Calling Render method like below:
outputarray = currentComponent.renderElement(activity);
console.log('output', outputarray)
Expected Output:
[{"Active":1,"Id":1,"Param1": true},
{"Active":1,"Id":3}, / Keep it as such if nothing exists in other array
{"Active":1,"Id":2, "Param2": false}]

You can try this approach instead:
Example #1
const arr1 = [
{ "Active":1, "Id":1 },
{ "Active":1, "Id":3 },
{ "Active":1, "Id":2 }
];
const arr2 = [
{
0: [
{
EmpId1: 1, Param1: true
}
]
},
{
1: [
{
EmpId2: 2,Param2: false
}
]
},
{
2: [
{
EmpId3: 2
}
]
},
];
const response = arr1
.reduce((acc, value) => {
const secondaryData = arr2.map((val, index) => {
const { [`EmpId${index + 1}`]: Id, ...others } = val[Object.keys(val)][0];
return { Id, ...others };
});
const match = secondaryData.findIndex(({ Id }) => Id === value.Id);
if (match >= 0) acc.push({...value, ...secondaryData[match]})
else acc.push(value);
return acc;
}, []);
console.log(response);
Example #2
const arr1 = [
{ "Active":1, "Id":1 },
{ "Active":1, "Id":3 },
{ "Active":1, "Id":2 }
];
const arr2 = [
[
{
EmpId1: 1,
Param1: true
}
],
[
{
EmpId2: 2,
Param2: false
}
],
[
{
EmpId3: 2
}
],
]
const response = arr1
.reduce((acc, value) => {
const secondaryData = arr2.map(([val], index) => {
const { [`EmpId${index + 1}`]: Id, ...others } = val;
return { Id, ...others };
});
const match = secondaryData.findIndex(({ Id }) => Id === value.Id);
if (match >= 0) acc.push({...value, ...secondaryData[match]})
else acc.push(value);
return acc;
}, []);
console.log(response);

Basically you can create a hash map by a object property and join on that property all the arrays, i.e. reduce an array of arrays into a result object, then convert the object's values back to an array. Since each array is reduced this means each array is only traversed once O(n) and the map object provides constant time O(1) lookup to match objects. This keeps the solution closer to O(n) rather than other solutions with a nested O(n) findIndex search, which yields a solution closer to O(n^2).
const mergeByField = (...arrays) => {
return Object.values(
arrays.reduce(
(result, { data, field }) => ({
...data.flat().reduce(
(obj, el) => ({
...obj,
[el[field]]: {
...obj[el[field]],
...el
}
}),
result
)
}),
{}
)
);
};
Load each array into a payload object that specifies the field key to match on. This will return all fields used to match by, but these can safely be ignored later, or removed, whatever you need. Example:
mergeByField(
{ data: arr1, field: "Id" },
{ data: arr2, field: "EmpId" },
);
const arr1 = [
{
Active: 1,
Id: 1
},
{
Active: 1,
Id: 2
},
{
Active: 1,
Id: 3
}
];
const arr2 = [[{ EmpId: 1, Param1: true }], [{ EmpId: 3, Param2: false }]];
const mergeByField = (...arrays) => {
return Object.values(
arrays.reduce(
(result, { data, field }) => ({
...data.flat().reduce(
(obj, el) => ({
...obj,
[el[field]]: {
...obj[el[field]],
...el
}
}),
result
)
}),
{}
)
);
};
console.log(
mergeByField({ data: arr1, field: "Id" }, { data: arr2, field: "EmpId" })
);

Merge Array of same level

I have an array which I need to combine with comma-separated of the same level and form a new array.
Input:
let arr = [
[{ LEVEL: 1, NAME: 'Mark' }, { LEVEL: 1, NAME: 'Adams' }, { LEVEL: 2, NAME: 'Robin' }],
[{ LEVEL: 3, NAME: 'Williams' }],
[{ LEVEL: 4, NAME: 'Matthew' }, { LEVEL: 4, NAME: 'Robert' }],
];
Output
[
[{ LEVEL: 1, NAME: 'Mark,Adams' }, { LEVEL: 2, NAME: 'Robin' }],
[{ LEVEL: 3, NAME: 'Williams' }],
[{ LEVEL: 4, NAME: 'Matthew,Robert' }],
];
I tried with the following code but not getting the correct result
let finalArr = [];
arr.forEach(o => {
let temp = finalArr.find(x => {
if (x && x.LEVEL === o.LEVEL) {
x.NAME += ', ' + o.NAME;
return true;
}
if (!temp) finalArr.push(o);
});
});
console.log(finalArr);

You could map the outer array and reduce the inner array by finding the same level and add NAME, if found. Otherwise create a new object.
var data = [[{ LEVEL: 1, NAME: "Mark" }, { LEVEL: 1, NAME: "Adams" }, { LEVEL: 2, NAME: "Robin"}], [{ LEVEL: 3, NAME: "Williams" }], [{ LEVEL: 4, NAME: "Matthew" }, { LEVEL: 4, NAME: "Robert" }]],
result = data.map(a => a.reduce((r, { LEVEL, NAME }) => {
var temp = r.find(q => q.LEVEL === LEVEL);
if (temp) temp.NAME += ',' + NAME;
else r.push({ LEVEL, NAME });
return r;
}, []));
console.log(result);
.as-console-wrapper { max-height: 100% !important; top: 0; }

Assuming you only want to merge within the same array and not across arrays, and assuming there aren't all that many entries (e.g., fewer than several hundred thousand), the simple thing is to build a new array checking to see if it already has the same level in it:
let result = arr.map(entry => {
let newEntry = [];
for (const {LEVEL, NAME} of entry) {
const existing = newEntry.find(e => e.LEVEL === LEVEL);
if (existing) {
existing.NAME += "," + NAME;
} else {
newEntry.push({LEVEL, NAME});
}
}
return newEntry;
});
let arr= [
[{"LEVEL":1,"NAME":"Mark"},
{"LEVEL":1,"NAME":"Adams"},
{"LEVEL":2,"NAME":"Robin"} ],
[{"LEVEL":3,"NAME":"Williams"}],
[{"LEVEL":4,"NAME":"Matthew"},
{"LEVEL":4,"NAME":"Robert"}]
];
let result = arr.map(entry => {
let newEntry = [];
for (const {LEVEL, NAME} of entry) {
const existing = newEntry.find(e => e.LEVEL === LEVEL);
if (existing) {
existing.NAME += "," + NAME;
} else {
newEntry.push({LEVEL, NAME});
}
}
return newEntry;
});
console.log(result);
If the nested arrays can be truly massively long, you'd want to build a map rather than doing the linear search (.find) each time.

I'd try to do as much of this in constant time as possible.
var m = new Map();
array.forEach( refine.bind(m) );
function refine({ LABEL, NAME }) {
var o = this.get(NAME)
, has = !!o
, name = NAME
;
if (has) name = `${NAME}, ${o.NAME}`;
this.delete(NAME);
this.set(name, { NAME: name, LABEL });
}
var result = Array.from( m.values() );
I haven't tested this as I wrote it on my phone at the airport, but this should at least convey the approach I would advise.
EDIT
Well... looks like the question was edited... So... I'd recommend adding a check at the top of the function to see if it's an array and, if so, call refine with an early return. Something like:
var m = new Map();
array.forEach( refine.bind(m) );
function refine(item) {
var { LABEL, NAME } = item;
if (!NAME) return item.forEach( refine.bind(this) ); // assume array
var o = this.get(NAME)
, has = !!o
, name = NAME
;
if (has) name = `${NAME}, ${o.NAME}`;
this.delete(NAME);
this.set(name, { NAME: name, LABEL });
}
var result = Array.from( m.values() );
That way, it should work with both your original question and your edit.
EDIT
Looks like the question changed again... I give up.

Map the array values: every element to an intermediate object, then create the desired object from the resulting entries:
const basicArr = [
[{"LEVEL":1,"NAME":"Mark"},
{"LEVEL":1,"NAME":"Adams"},
{"LEVEL":2,"NAME":"Robin"} ],
[{"LEVEL":3,"NAME":"Williams"}],
[{"LEVEL":4,"NAME":"Matthew"},
{"LEVEL":4,"NAME":"Robert"}]
];
const leveled = basicArr.map( val => {
let obj = {};
val.forEach(v => {
obj[v.LEVEL] = obj[v.LEVEL] || {NAME: []};
obj[v.LEVEL].NAME = obj[v.LEVEL].NAME.concat(v.NAME);
});
return Object.entries(obj)
.map( ([key, val]) => ({LEVEL: +key, NAME: val.NAME.join(", ")}));
}
);
console.log(leveled);
.as-console-wrapper { top: 0; max-height: 100% !important; }
if you want to flatten all levels
const basicArr = [
[{"LEVEL":1,"NAME":"Mark"},
{"LEVEL":1,"NAME":"Adams"},
{"LEVEL":2,"NAME":"Robin"} ],
[{"LEVEL":3,"NAME":"Williams"}],
[{"LEVEL":4,"NAME":"Matthew"},
{"LEVEL":4,"NAME":"Robert"},
{"LEVEL":2,"NAME":"Cynthia"}],
[{"LEVEL":3,"NAME":"Jean"},
{"LEVEL":4,"NAME":"Martha"},
{"LEVEL":2,"NAME":"Jeff"}],
];
const leveled = basicArr.map( val => Object.entries (
val.reduce( (acc, val) => {
acc[val.LEVEL] = acc[val.LEVEL] || {NAME: []};
acc[val.LEVEL].NAME = acc[val.LEVEL].NAME.concat(val.NAME);
return acc;
}, {}))
.map( ([key, val]) => ({LEVEL: +key, NAME: val.NAME.join(", ")})) )
.flat() // (use .reduce((acc, val) => acc.concat(val), []) for IE/Edge)
.reduce( (acc, val) => {
const exists = acc.filter(x => x.LEVEL === val.LEVEL);
if (exists.length) {
exists[0].NAME = `${val.NAME}, ${exists.map(v => v.NAME).join(", ")}`;
return acc;
}
return [... acc, val];
}, [] );
console.log(leveled);
.as-console-wrapper { top: 0; max-height: 100% !important; }

ES6 way:
let say attributes is multidimensional array having multimple entries which need to combine like following:
let combinedArray = [];
attributes.map( attributes => {
combined = combinedArray.concat(...attributes);
});

Javascript how to join two arrays having same property value?

How do I join arrays with the same property value? I cannot map it because it has different indexes.
var array1 = [
{'label':"label1",'position':0},
{'label':"label3",'position':2},
{'label':"label2",'position':1},
];
var array2 = [
{'label':"label1",'value':"TEXT"},
{'label':"label2",'value':"SELECT"}
];
expected output:
var array3 = [
{'label':"label1",'value':"TEXT",'position':0},
{'label':"label2",'value':"SELECT", 'position':1}
];
This is what I did, I cannot make it work,
var arr3 = arr1.map(function(v, i) {
return {
"label": v.label,
"position": v.position,
"value": arr2[?].value
}
});

I think you can use array#reduce to do something like this perhaps:
var array1 = [
{'label':"label1",'position':0},
{'label':"label3",'position':2},
{'label':"label2",'position':1},
];
var array2 = [
{'label':"label1",'value':"TEXT"},
{'label':"label2",'value':"SELECT"}
];
var array3 = array2.reduce((arr, e) => {
arr.push(Object.assign({}, e, array1.find(a => a.label == e.label)))
return arr;
}, [])
console.log(array3);

You could take a Map and check the existence for a new object.
var array1 = [{ label: "label1", position: 0 }, { label: "label3", position: 2 }, { label: "label2", position: 1 }],
array2 = [{ label: "label1", value: "TEXT" }, { label: "label2", value: "SELECT" }],
map = array1.reduce((m, o) => m.set(o.label, o), new Map),
array3 = array2.reduce((r, o) => {
if (map.has(o.label)) {
r.push(Object.assign({}, o, map.get(o.label)));
}
return r;
}, []);
console.log(array3);
.as-console-wrapper { max-height: 100% !important; top: 0; }

As per the effort, we take an assumption that array1 will be having all the labels that are in array2.
Based on that first, create a map for array2and with key being labels. Post that, filter out array1 items which have labels existing in the map and then finally merging the objects of the filtered array and its corresponding values in map extracted from array2.
var array1 = [{'label':"label1",'position':0},{'label':"label3",'position':2},{'label':"label2",'position':1}];
var array2 = [{'label':"label1",'value':"TEXT"},{'label':"label2",'value':"SELECT"}];
let map = array2.reduce((a,{label, ...rest}) => Object.assign(a,{[label]:rest}),{});
let result = array1.filter(({label}) => map[label]).map(o => ({...o, ...map[o.label]}));
console.log(result);
Also, in the above snippet, you can improve the performance further by using Array.reduce against filter and map functions to retrieve the result.
var array1 = [{'label':"label1",'position':0},{'label':"label3",'position':2},{'label':"label2",'position':1}];
var array2 = [{'label':"label1",'value':"TEXT"},{'label':"label2",'value':"SELECT"}];
let map = array2.reduce((a,{label, ...rest}) => Object.assign(a,{[label]:rest}),{});
let result = array1.reduce((a,o) => {
if(map[o.label]) a.push({...o, ...map[o.label]});
return a;
}, []);
console.log(result);

If you don't know in advance which array(s) will have their labels be a subset of the other (if any), here's a method that allows for either array1 or array2 to have labels that the other array lacks. Use reduce over array1, finding the matching label in array2 if it exists:
var array1 = [
{'label':"label1",'position':0},
{'label':"label3",'position':2},
{'label':"label2",'position':1},
];
var array2 = [
{'label':"label1",'value':"TEXT"},
{'label':"label2",'value':"SELECT"}
];
const output = array1.reduce((a, { label, position }) => {
const foundValueObj = array2.find(({ label: findLabel }) => findLabel === label);
if (!foundValueObj) return a;
const { value } = foundValueObj;
a.push({ label, value, position });
return a;
}, []);
console.log(output);

See Array.prototype.map() and Map for more info.
// Input.
const A = [{'label':"label1",'position':0},{'label':"label3",'position':2},{'label':"label2",'position':1}]
const B = [{'label':"label1",'value':"TEXT"},{'label':"label2",'value':"SELECT"}]
// Merge Union.
const mergeUnion = (A, B) => {
const mapA = new Map(A.map(x => [x.label, x]))
return B.map(y => ({...mapA.get(y.label), ...y}))
}
// Output + Proof.
const output = mergeUnion(A, B)
console.log(output)

This works.
Approach: Concatenate the objects with same label, using Object.assign()
var array1 = [{'label':"label1",'position':0},{'label':"label3",'position':2},{'label':"label2",'position':1}];
var array2 = [{'label':"label1",'value':"TEXT"},{'label':"label2",'value':"SELECT"}];
var result = [];
array2.forEach(function(value, index){
result.push(Object.assign({},array1.find(function(v,i){return v.label==value.label}),value));
});
console.log(result)

Im not good with javascript,but you could also do this
var array1 = [
{'label':"label1",'position':0},
{'label':"label3",'position':2},
{'label':"label2",'position':1},
];
var array2 = [
{'label':"label1",'value':"TEXT"},
{'label':"label2",'value':"SELECT"}
];
var array3=[];
for(var i=0;i<array1.length;i++)
{
for(var x=0;x<array2.length;x++)
{
console.log(array1[i]['label'] == array2[x]['label']);
if(array1[i]['label'] == array2[x]['label']){
array3.push({label:array1[i]['label'],value:array2[x]['value'],position:array1[i]['position']});
}
}
}
console.log(array3);

Sort a list by property and add an object before each first letter changes in JavaScript

So I am trying to make a UI like this:
And I have an array of users
[{name: 'Julia'}, {name: 'Ismeh'}, {name: 'Alison'}, {name: 'Andrea'}, {name: 'Betty'}]
What I am trying to do is to sort the array by first letter of the name property, and add a header object before each. For example in the picture, you can see the letter A, B, I, and J as the headers.
For now, I got it working like this:
let final = []
// sort by first letter
const sortedUsers = state.test_list.sort((a, b) => a.name.localeCompare(b.name))
for (let x = 0; x < sortedUsers.length; x++) {
const user = sortedUsers[x].name
if (user.charAt(0) === 'A') {
const checkIfExists = final.findIndex((f) => f.header === 'A')
// add the header A if it doesn't exist
if (checkIfExists < 0) final.push({header: 'A'})
}
else if (user.charAt(0) === 'B') {
const checkIfExists = final.findIndex((f) => f.header === 'B')
// add the header B if it doesn't exist
if (checkIfExists < 0) final.push({header: 'B'})
}
// else if up to the letter Z
final.push(user)
}
and if I log the final array, I get:
which is correct.
My concern is that the code is very long, and I have no idea if it can be optimized or make the code smaller.
Is there any other option to do something like this? Any help would be much appreciated.

Why don't you create a collection of names, which is grouped by the first letter? You can then loop on it, and create your list. Use Array#reduce to create the grouped collection.
And then use Object#keys to iterate over the grouped collection and render your results:
let data = [{
name: 'Julia'
}, {
name: 'Ismeh'
}, {
name: 'Alison'
}, {
name: 'Andrea'
}, {
name: 'Betty'
}];
let combined = data.reduce((result, item) => {
let letter = item.name[0].toUpperCase();
if (!result[letter]) {
result[letter] = [];
}
result[letter].push(item);
return result;
}, {});
console.log(combined);
// Iterate over the result
Object.keys(combined).forEach(key => {
// key will be the first letter of the user names and
// combined[key] will be an array of user objects
console.log(key, combined[key]);
});
One thing still to do is to sort the user arrays by user name, which you can do easily using Array#sort.

Simple enough, try sorting them and then using .reduce:
const unsortedPeople = [{name: 'Julia'}, {name: 'Ismeh'}, {name: 'Alison'}, {name: 'Andrea'}, {name: 'Betty'}];
const sortedUsers = unsortedPeople.sort((a, b) => a.name.localeCompare(b.name))
const final = sortedUsers.reduce((finalSoFar, user) => {
const thisUserFirstChar = user.name[0];
if (finalSoFar.length === 0) addHeader();
else {
const lastUserFirstChar = finalSoFar[finalSoFar.length - 1].name[0];
if (lastUserFirstChar !== thisUserFirstChar) addHeader();
}
finalSoFar.push(user);
return finalSoFar;
function addHeader() {
finalSoFar.push({ header: thisUserFirstChar });
}
}, []);
console.log(final);

Why don't you just keep track of the current abbreviation as you loop. Then you can add a head when it changes:
var users = [{name: 'Julia'}, {name: 'Ismeh'}, {name: 'Alison'}, {name: 'Andrea'}, {name: 'Betty'}]
const sortedUsers = users.sort((a, b) => a.name.localeCompare(b.name))
var currentHeader
let final = sortedUsers.reduce((a, user) => {
if (currentHeader !== user.name[0]) {
currentHeader = user.name[0]
a.push({header: currentHeader})
}
a.push(user)
return a
},[])
console.log(final)

Here's one way to do it:
const users = [{name: 'Julia'}, {name: 'Ismeh'}, {name: 'Alison'}, {name: 'Andrea'}, {name: 'Betty'}];
let lastIndex;
let result = [];
users.sort((a, b) => {
return a.name > b.name;
}).forEach((user) => {
const index = user.name.charAt(0);
if (index !== lastIndex) {
result.push({
header: index
});
}
lastIndex = index;
result.push(user.name);
}, []);
console.log(result);

You can use _.orderBy(collection, [iteratees=[_.identity]], [orders]) and _.groupBy(collection, [iteratee=_.identity]) method of lodash.
This orderBy is like _.sortBy except that it allows specifying the sort orders of the iteratees to sort by. If orders is unspecified, all values are sorted in ascending order. Otherwise, specify an order of "desc" for descending or "asc" for ascending sort order of corresponding values.
groupBy will creates an object composed of keys generated from the results of running each element of collection thru iteratee. The order of grouped values is determined by the order they occur in collection. The corresponding value of each key is an array of elements responsible for generating the key. The iteratee is invoked with one argument: (value).
example
// The `_.property` iteratee shorthand.
_.groupBy(['one', 'two', 'three'], 'length');
// => { '3': ['one', 'two'], '5': ['three'] }
// Sort by `user` in ascending order and by `age` in descending order.
_.orderBy(users, ['user', 'age'], ['asc', 'desc']);
With lodash
let myArr = [{
name: 'Julia'
}, {
name: 'Ismeh'
}, {
name: 'Andrea'
}, {
name: 'Alison'
}, {
name: 'Betty'
}];
myArr = _.orderBy(myArr, ['name'], ['asc']);
let r = _.groupBy(myArr, o => {
return o.name.charAt(0).toUpperCase();
})
console.log(r);
<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.4/lodash.js"></script>
IN ES5
var arr = [{
name: 'Julia'
}, {
name: 'Ismeh'
}, {
name: 'Andrea'
}, {
name: 'Alison'
}, {
name: 'Betty'
}],
fChar = '';
arr = arr.sort(function(a, b) {
a = a.name.toUpperCase(); // ignore upper and lowercase
b = b.name.toUpperCase(); // ignore upper and lowercase
return a < b ? -1 : (a > b ? 1 : 0);
}).reduce(function(r, o) {
fChar = o.name.charAt(0).toUpperCase();
if (!r[fChar]) {
r[fChar] = [];
}
r[fChar].push({
name: o.name
});
return r;
}, {});
console.log(arr);
IN ES6
const arr = [{
name: 'Julia'
}, {
name: 'Ismeh'
}, {
name: 'Andrea'
}, {
name: 'Alison'
}, {
name: 'Betty'
}];
let result = arr.sort((a, b) => {
a = a.name.toUpperCase(); // ignore upper and lowercase
b = b.name.toUpperCase(); // ignore upper and lowercase
return a < b ? -1 : (a > b ? 1 : 0);
}).reduce((r, o) => {
let fChar = o.name.charAt(0).toUpperCase();
if (!r[fChar]) {
r[fChar] = [];
}
r[fChar].push({
name: o.name
});
return r;
}, {});
console.log(result);