how to get an index of an array if the checked value is in the nested array?

Question

I have an array like this

const myArray = [ [ false ], [ true ], [ false ] ]

i want to get index of an element that has value == true from array above.

so because the true from array above is in the second element, then I want to get 1 as the index result

how to do that ?

have you tried anything? what does not work? do you have only one array with true? — Nina Scholz
– Nina Scholz, Commented Jul 1, 2020 at 6:53
Does this answer your question? To find Index of Multidimensional Array in Javascript — Heretic Monkey
– Heretic Monkey, Commented Jul 1, 2020 at 16:24

Hasintha Janka · Accepted Answer · 2020-07-01 06:59:15Z

1

You just need add filter for this,

const myArray = [ [ false ], [ true ], [ false ] ] 

let result = myArray.filter(function(value) {
    return value[0]=== true;
});

answered Jul 1, 2020 at 6:59

Hasintha Janka

1,6391 gold badge14 silver badges29 bronze badges

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

1 Comment

see sharper Over a year ago

That returns a filtered array, not the index of the array with a true value.

eemmrrkk · Accepted Answer · 2020-07-01 07:04:30Z

1

const arrays = [ [ false ], [ true ], [ false ] ] 

const index = [].concat.apply([], arrays).findIndex(value => value === true)

edited Jul 1, 2020 at 7:04

answered Jul 1, 2020 at 6:59

eemmrrkk

1,7093 gold badges21 silver badges43 bronze badges

Comments

hamidreza nikoonia · Accepted Answer · 2020-07-01 06:55:38Z

0

you can loop on your array with map method


const arr = [ [ false ], [ true ], [ false ] ] 

arr.map((item, index) => {

if (item[0]) {
  console.log(index)
}

})

answered Jul 1, 2020 at 6:55

hamidreza nikoonia

2,1752 gold badges24 silver badges31 bronze badges

1 Comment

Nina Scholz Over a year ago

map returns a new array. if this is not used later, it makes no sense.

Donald Duck is with Ukraine · Accepted Answer · 2020-07-01 16:16:10Z

0

const idx = myArray.findIndex(i => i[0]);

edited Jul 1, 2020 at 16:16

Donald Duck is with Ukraine

9,00223 gold badges81 silver badges106 bronze badges

answered Jul 1, 2020 at 6:53

see sharper

12.2k8 gold badges53 silver badges68 bronze badges

3 Comments

Simone Rossaini Over a year ago

Post answer with only code is not good, please explains always your answer.

Donald Duck is with Ukraine Over a year ago

While this code may answer the question, providing additional context regarding how and/or why it solves the problem would improve the answer's long-term value.

see sharper Over a year ago

The code is so simple I would think it self explanatory, noting that the other answers either offer no explanation, or a rather redundant one-liner. IMO this is still the best answer. The accepted answer is plain wrong, and the other upvoted answer uses a hard to read array flattening technique that does need explanation.

Collectives™ on Stack Overflow

how to get an index of an array if the checked value is in the nested array?

4 Answers 4

1 Comment

Comments

1 Comment

3 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

1 Comment

Comments

1 Comment

3 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related