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I have an array of objects, however i need the array to add a count onto each object, and also remove any duplicates. Is there a simple way to achieve this?
CURRENT
[
{ id: 2, name: 'Adventure' },
{ id: 6, name: 'Crime' },
{ id: 2, name: 'Adventure' },
{ id: 3, name: 'Beautiful' },
{ id: 7, name: 'Drama' },
{ id: 2, name: 'Adventure' }
]
EXPECTED
[
{ id: 2, name: 'Adventure', count: 3 },
{ id: 6, name: 'Crime', count: 1 },
{ id: 3, name: 'Beautiful', count: 1 },
{ id: 7, name: 'Drama', count: 1 }
]
let current = [
{ id: 2, name: 'Adventure' },
{ id: 6, name: 'Crime' },
{ id: 2, name: 'Adventure' },
{ id: 3, name: 'Beautiful' },
{ id: 7, name: 'Drama' },
{ id: 2, name: 'Adventure' }
]
let expected = current.reduce((acc, cur) => {
let curFind = acc.find(item => item.id === cur.id)
if (curFind) {
curFind.count++
return acc
} else {
return [...acc, {
...cur,
count: 1
}]
}
}, [])
console.log('expected:', expected)
Not getting all matched objects, its is returning all objects except '{ ID:0, Name: 'General Group' }', i want all matched objects
let arrDashboardIconGroups = [
{ ID:0, Name: 'General Group' },
{ ID: 1, Name: 'Patient Administration' },
{ ID: 2, Name: 'Medical Charts' },
{ ID: 3, Name: 'Medical Procedures' },
{ ID: 13, Name: 'Purchase' },
{ ID: 14, Name: 'Sales' },
{ ID: 5, Name: 'Insurance' },
{ ID: 4, Name: 'Cash' },
{ ID: 6, Name: 'Pharmacy' },
{ ID: 7, Name: 'Inventory' },
{ ID: 8, Name: 'Lab' },
{ ID: 9, Name: 'Imaging' },
{ ID: 10, Name: 'In Patient' },
{ ID: 11, Name: 'System Administration' },
{ ID: 12, Name: 'Accounting' }
]
const getMatchedobjects=()=> {
let result = [0,1,2,3,4,]
let matchedArray = arrDashboardIconGroups.filter(val =>result.find(
(items)=>items == val.ID))
console.log(matchedArray)
}
getMatchedobjects()
You are returning the value of
result.find((items) => items == val.ID)
In the first case, the value returned is 0 which is a falsy value. So It won't include in the final filter result.
You can run the below code and see the returning values.
let arrDashboardIconGroups = [
{ ID: 0, Name: "General Group" },
{ ID: 1, Name: "Patient Administration" },
{ ID: 2, Name: "Medical Charts" },
{ ID: 3, Name: "Medical Procedures" },
{ ID: 13, Name: "Purchase" },
{ ID: 14, Name: "Sales" },
{ ID: 5, Name: "Insurance" },
{ ID: 4, Name: "Cash" },
{ ID: 6, Name: "Pharmacy" },
{ ID: 7, Name: "Inventory" },
{ ID: 8, Name: "Lab" },
{ ID: 9, Name: "Imaging" },
{ ID: 10, Name: "In Patient" },
{ ID: 11, Name: "System Administration" },
{ ID: 12, Name: "Accounting" },
];
const getMatchedobjects = () => {
let result = [0, 1, 2, 3, 4];
let matchedArray = arrDashboardIconGroups.filter((val) => {
const returnResult = result.find((items) => items == val.ID);
console.log(returnResult);
return returnResult;
// result.includes(val.ID)
});
console.log(matchedArray);
};
getMatchedobjects();
Alternatively, you can use includes
let arrDashboardIconGroups = [
{ ID: 0, Name: "General Group" },
{ ID: 1, Name: "Patient Administration" },
{ ID: 2, Name: "Medical Charts" },
{ ID: 3, Name: "Medical Procedures" },
{ ID: 13, Name: "Purchase" },
{ ID: 14, Name: "Sales" },
{ ID: 5, Name: "Insurance" },
{ ID: 4, Name: "Cash" },
{ ID: 6, Name: "Pharmacy" },
{ ID: 7, Name: "Inventory" },
{ ID: 8, Name: "Lab" },
{ ID: 9, Name: "Imaging" },
{ ID: 10, Name: "In Patient" },
{ ID: 11, Name: "System Administration" },
{ ID: 12, Name: "Accounting" },
];
const getMatchedobjects = () => {
let result = [0, 1, 2, 3, 4];
let matchedArray = arrDashboardIconGroups.filter((val) => result.includes(val.ID));
console.log(matchedArray);
};
getMatchedobjects();
Issue
Find returns a value/object (the first matching), but it seems you want to filter the arrDashboardIconGroups array by those that match an id specified in the result array. When result[0] is returned, 0 is the value, which is falsey, and the filter doesn't return the element from the arrDashboardIconGroups array.
Solution
Use Array.prototype.some to return the boolean that filter needs to include an element in the result array.
let arrDashboardIconGroups = [
{ ID:0, Name: 'General Group' },
{ ID: 1, Name: 'Patient Administration' },
{ ID: 2, Name: 'Medical Charts' },
{ ID: 3, Name: 'Medical Procedures' },
{ ID: 13, Name: 'Purchase' },
{ ID: 14, Name: 'Sales' },
{ ID: 5, Name: 'Insurance' },
{ ID: 4, Name: 'Cash' },
{ ID: 6, Name: 'Pharmacy' },
{ ID: 7, Name: 'Inventory' },
{ ID: 8, Name: 'Lab' },
{ ID: 9, Name: 'Imaging' },
{ ID: 10, Name: 'In Patient' },
{ ID: 11, Name: 'System Administration' },
{ ID: 12, Name: 'Accounting' }
];
const getMatchedobjects = () => {
let result = [0,1,2,3,4,];
let matchedArray = arrDashboardIconGroups.filter(val => result.some((items)=>items == val.ID));
console.log(matchedArray);
}
getMatchedobjects();
Alternatively you could also check that result array includes the matching id.
let arrDashboardIconGroups = [
{ ID:0, Name: 'General Group' },
{ ID: 1, Name: 'Patient Administration' },
{ ID: 2, Name: 'Medical Charts' },
{ ID: 3, Name: 'Medical Procedures' },
{ ID: 13, Name: 'Purchase' },
{ ID: 14, Name: 'Sales' },
{ ID: 5, Name: 'Insurance' },
{ ID: 4, Name: 'Cash' },
{ ID: 6, Name: 'Pharmacy' },
{ ID: 7, Name: 'Inventory' },
{ ID: 8, Name: 'Lab' },
{ ID: 9, Name: 'Imaging' },
{ ID: 10, Name: 'In Patient' },
{ ID: 11, Name: 'System Administration' },
{ ID: 12, Name: 'Accounting' }
];
const getMatchedobjects=()=> {
let result = [0,1,2,3,4,];
let matchedArray = arrDashboardIconGroups.filter(val => result.includes(val.ID)) ;
console.log(matchedArray);
}
getMatchedobjects();
find() returns value of the first element in the provided array that satisfies the provided testing function. Since 0 is a falsy value, it does not include it in the final array. See MDN Docs
You can map the result array, and use arrDashboardIconGroups's find function, and return the matching objects.
let arrDashboardIconGroups = [
{ ID: 0, Name: 'General Group' },
{ ID: 1, Name: 'Patient Administration' },
{ ID: 2, Name: 'Medical Charts' },
{ ID: 3, Name: 'Medical Procedures' },
{ ID: 13, Name: 'Purchase' },
{ ID: 14, Name: 'Sales' },
{ ID: 5, Name: 'Insurance' },
{ ID: 4, Name: 'Cash' },
{ ID: 6, Name: 'Pharmacy' },
{ ID: 7, Name: 'Inventory' },
{ ID: 8, Name: 'Lab' },
{ ID: 9, Name: 'Imaging' },
{ ID: 10, Name: 'In Patient' },
{ ID: 11, Name: 'System Administration' },
{ ID: 12, Name: 'Accounting' }
]
const getMatchedobjects=()=> {
let result = [0, 1,2,3,4,99] //99 for trial
let matchedArray = result.map((res)=>arrDashboardIconGroups.find((val)=>val.ID == res)).filter(Boolean);
console.log(matchedArray)
}
getMatchedobjects()
How do I flatten the nested Array in the Array?
Here is the example input Array,
const input = [
{
id: 1,
name: 'Charles',
otherFields: [{
id: 2,
name: 'Pung',
}, {
id: 3,
name: 'James',
}]
}, {
id: 4,
name: 'Charles',
otherFields: [{
id: 5,
name: 'Pung',
}, {
id: 6,
name: 'James',
}]
}
]
Output Array I want to get.
[{
id: 1,
name: 'Charles'
}, {
id: 2,
name: 'Pung',
}, {
id: 3,
name: 'James',
}, {
id: 4,
name: 'Charles'
}, {
id: 5,
name: 'Pung',
}, {
id: 6,
name: 'James',
}]
I want to somehow get the output in one statement like
input.map((sth) => ({...sth??, sth.field...})); // I'm not sure :(
With flatMap you can take out the otherFields property, and returning an array containing the parent item and the other array:
const input = [{
id: 1,
name: 'Charles',
otherFields: [{
id: 2,
name: 'Pung',
}, {
id: 3,
name: 'James',
}]
}];
console.log(
input.flatMap(({ otherFields, ...item }) => [item, ...otherFields])
);
For more than one level, you could take a recursive approach of flattening.
const
flat = ({ otherFields = [], ...o }) => [o, ...otherFields.flatMap(flat)],
input = [{ id: 1, name: 'Charles', otherFields: [{ id: 2, name: 'Pung' }, { id: 3, name: 'James', otherFields: [{ id: 4, name: 'Jane' }] }] }],
result = input.flatMap(flat);
console.log(result);
.as-console-wrapper { max-height: 100% !important; top: 0; }
I have static array constant of objects something similar to below.
export const EMPLOYEES = [
{
id: 2,
name: ‘John’,
},
{
id: 3,
name: ‘Doe’,
},
{
id: 4,
name: ‘Bull’,
},
{
id: 5,
name: ‘Scott’,
},
];
Now I need to add the last element only based on if some condition is true. Some this like if isAmerican() is true.
Can somebody help me here how to add element based on the condition? Thanks.
You can do it using spread operator:
export const EMPLOYEES = [
{
id: 2,
name: "John",
},
{
id: 3,
name: "Doe",
},
{
id: 4,
name: "Bull",
},
{
id: 5,
name: "Scott",
},
... isAmerican() ? [{ id: 6, name: "Jemmy"}] : []
];
You should never modify (or try to modify) a constant. I can see two ways you can do this:
Create a pure function to return a new constant with the new object added to the array
Use a spread operator in the definition of the constant
Option 1: Pure function
function makeNewArray(array, objectToAppend, isAmerican) {
return isAmerican ? [...array, objectToAppend] : array
}
const EMPLOYEES = [
{
id: 2,
name: "John",
},
{
id: 3,
name: "Doe",
},
{
id: 4,
name: "Bull",
},
{
id: 5,
name: "Scott",
}
];
const arrayWithAmerican = makeNewArray(EMPLOYEES, { id: 6, name: "American Frank"}, true);
const arrayWithoutAmerican = makeNewArray(EMPLOYEES, { id: 6, name: "Not American Frank"}, false);
console.log(arrayWithAmerican);
console.log(arrayWithoutAmerican);
Option 2: Spread operator
function isAmerican(){
// generic code here.
return true;
}
const EMPLOYEES = [
{
id: 2,
name: "John",
},
{
id: 3,
name: "Doe",
},
{
id: 4,
name: "Bull",
},
{
id: 5,
name: "Scott",
},
... isAmerican() ? [{ id: 6, name: "American Frank"}] : []
];
If the condition will be fulfilled, simply push an object to your EMPLOYEES array:
let isAmerican = true;
const EMPLOYEES = [
{
id: 2,
name: "John",
},
{
id: 3,
name: "Doe",
},
{
id: 4,
name: "Bull",
},
{
id: 5,
name: "Scott",
},
];
if(isAmerican) {
EMPLOYEES.push({
id: 6,
name: "Frank"
})
}
console.log(EMPLOYEES)
Fiddle: https://jsfiddle.net/rqx35pLz/
I want to unwind an array of objects which have arrays of objects nested. The level of nesting is not defined and is not consistent throughout the array.
Here's my sample data
var data = [{
id: 1,
name: 'Harshal',
subjects: [{
id: 1,
name: 'English',
chapters: [{
id: 1,
name: 'Grammar'
}, {
id: 2,
name: 'Comprehension'
}]
}, {
id: 2,
name: 'Maths',
chapters: [{
id: 1,
name: 'Algebra'
}, {
id: 2,
name: 'Geometry'
}]
}]
}, {
id: 2,
name: 'Pankaj',
subjects: [{
id: 3,
name: 'Marathi',
chapters: [{
id: 1,
name: 'Kavita',
topics: [{
id: 1,
name: 'Topic 1'
}]
}]
}, {
id: 4,
name: 'Hindi',
chapters: [{
id: 1,
name: 'Katha',
topics: [{
id: 2,
name: 'Topic 2'
}, {
id: 3,
name: 'Topic 3'
}]
}]
}]
}];
I want to get an output like this:
var op = [{
id: 1,
name: 'Harshal',
subjects: {
id: 1,
name: 'English',
chapters: {
id: 1,
name: 'Grammar'
}
}
}, {
id: 1,
name: 'Harshal',
subjects: {
id: 1,
name: 'English',
chapters: {
id: 2,
name: 'Comprehension'
}
}
}, {
id: 1,
name: 'Harshal',
subjects: {
id: 2,
name: 'Maths',
chapters: {
id: 1,
name: 'Algebra'
}
}
}, {
id: 1,
name: 'Harshal',
subjects: {
id: 2,
name: 'Maths',
chapters: {
id: 2,
name: 'Geometry'
}
}
}, {
id: 2,
name: 'Pankaj',
subjects: {
id: 3,
name: 'Marathi',
chapters: {
id: 1,
name: 'Kavita',
topics: {
id: 1,
name: 'Topic 1'
}
}
}
}, {
id: 2,
name: 'Pankaj',
subjects: {
id: 4,
name: 'Hindi',
chapters: {
id: 1,
name: 'Katha',
topics: {
id: 2,
name: 'Topic 2'
}
}
}
}, {
id: 2,
name: 'Pankaj',
subjects: {
id: 4,
name: 'Hindi',
chapters: {
id: 1,
name: 'Katha',
topics: {
id: 3,
name: 'Topic 3'
}
}
}
}];
I have tried to work with pull-unwind but I guess there's some issues with it. If anyone has any other ideas, I'm open to implement those.
Have you tried recursion?
var data = [{
id: 1,
name: 'Harshal',
subjects: [{
id: 1,
name: 'English',
chapters: [{
id: 1,
name: 'Grammar'
}, {
id: 2,
name: 'Comprehension'
}]
}, {
id: 2,
name: 'Maths',
chapters: [{
id: 1,
name: 'Algebra'
}, {
id: 2,
name: 'Geometry'
}]
}]
}, {
id: 2,
name: 'Pankaj',
subjects: [{
id: 3,
name: 'Marathi',
chapters: [{
id: 1,
name: 'Kavita',
topics: [{
id: 1,
name: 'Topic 1'
}]
}]
}, {
id: 4,
name: 'Hindi',
chapters: [{
id: 1,
name: 'Katha',
topics: [{
id: 2,
name: 'Topic 2'
}, {
id: 3,
name: 'Topic 3'
}]
}]
}]
}];
function unravel(obj)
{
var out = [];
var added = false;
for(var i in obj) {
if(obj[i] instanceof Array) {
for(var j in obj[i]) {
var r = unravel(obj[i][j]);
for(var k in r) {
var a = {};
for(var key in obj) { // make copy of obj
a[key] = obj[key];
}
a[i] = r[k];
added = true;
out.push(a);
}
}
}
}
if(!added) {
out.push(obj);
}
return out;
}
var op = [];
for(var i in data)
op = op.concat(unravel(data[i]));
console.log(JSON.stringify(op, null, 4));