Loop over an array and return an array of each element in the array

Question

I have an array that I am mapping over to create a list. When a user clicks one element I need to create an array with the index of all elements in that array. Then if an item at one of those indexes is clicked it is removed from the array. I am having trouble figuring out a method for creating the array of all indexes. My component is being sent each index one by one from a map so Ive tried pushing each index into an array but I end up with an array with only 1 index:

items = [{type
items.map((item, idx) => {
let indexes = [{type: "clickable", time: "11:41pm"}{type: "standard", time: "11:42pm"},{type: "clickable", time: "11:43pm"}, {type: "clickable", time: "11:45pm"}]

if(item.type == "clicklable"){
  indexs.push(idx)
}
console.log(indexes)
// [0]
// [2]
// [3]
}

How can I add all the indexes to one array?

A1exandr Belan · Accepted Answer · 2022-08-12 05:24:56Z

2

You can use .flatMap to map index and filter array at the same time.

const indexes = [{type: "clickable", time: "11:41pm"},{type: "standard", time: "11:42pm"},{type: "clickable", time: "11:43pm"},{type: "clickable", time: "11:45pm"}];

const clickableIndexes = indexes.flatMap(({ type }, idx) => type === 'clickable' ? idx : []);

console.log(clickableIndexes);

.as-console-wrapper { max-height: 100% !important; top: 0 }

answered Aug 12, 2022 at 5:24

A1exandr Belan

4,7803 gold badges30 silver badges53 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

jagan · Accepted Answer · 2022-08-12 05:16:26Z

0

Please try this:

let indexes = [{type: "clickable", time: "11:41pm"},{type: "standard", time: "11:42pm"},{type: "clickable", time: "11:43pm"}, {type: "clickable", time: "11:45pm"}]
let indexs=[]
indexes.map((item)=>{
    indexs.push(item.type)
})
console.log(indexs)

answered Aug 12, 2022 at 5:16

jagan

12 bronze badges

1 Comment

Community Over a year ago

Your answer could be improved with additional supporting information. Please edit to add further details, such as citations or documentation, so that others can confirm that your answer is correct. You can find more information on how to write good answers in the help center.

Dylan Dang · Accepted Answer · 2022-08-12 05:45:03Z

0

You can try mapping each item to either their index number or false with short circuiting and then filtering by Number.isInteger

const items = [
    { type: 'clickable', time: '11:41pm' },
    { type: 'standard', time: '11:42pm' },
    { type: 'clickable', time: '11:43pm' },
    { type: 'clickable', time: '11:45pm' },
];

const indices = items.map((item, idx) => item.type === 'clickable' && idx)
    .filter(Number.isInteger);
    
console.log(indices);

edited Aug 12, 2022 at 5:45

answered Aug 12, 2022 at 5:27

Dylan Dang

1664 bronze badges

Collectives™ on Stack Overflow

Loop over an array and return an array of each element in the array

3 Answers 3

Comments

1 Comment

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

Comments

1 Comment

Comments

Your Answer

Sign up or log in

Post as a guest

Related