Check equality to a set of values in an array with a specific value and return index

Question

I have a following array: [400, 600, 1000] - I need to see a changing/dynamic value against this array if it equals to any of the values inside the array and return the index of the value matched.

Tried:

arr.every(x => x = dynamicValue );

This return boolean

`arr.every(x => x = dynamicValue );` is setting a value, you need to use the equality operator `arr.every(x => x === dynamicValue );` — Ryan Wilson, Dec 07 '18 at 20:40
@monkeyjs it will give index of match if not than -1. in case you want bool you can use includes — Code Maniac, Dec 07 '18 at 20:43

StepUp · Answer 1 · 2018-12-08T11:40:03.213

1

If you want to find index:

let yourArray = [400, 600, 1000];
let yourVariable = 600;
let indexElement = yourArray.indexOf(yourVariable);

UPDATE:

To get indexes of wish elements of array:

let yourArray = [400, 600, 1000];    
let yourVariable = 1000;
let yourIndexes = [];
yourArray.forEach((e, i)=>{
        if(e < yourVariable) 
            yourIndexes.push(i);
    });

edited Dec 08 '18 at 11:40

answered Dec 07 '18 at 20:47

StepUp

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@https://stackoverflow.com/users/1646240/stepup Is there a way I get all indices that are less than 600 here? filter returns updated array with matched values - but how to get the indices - here I need to get [0,1] - when checked value in array – monkeyjs Dec 07 '18 at 21:31
@monkeyjs please, see my updated answer. – StepUp Dec 07 '18 at 21:47
works like charm. Thank you so much @StepUp. – monkeyjs Dec 07 '18 at 22:27
@monkeyjs I've found a bag in my implementation. Now it works properly. See necessary indexes in `yourIndexes` array. Feel free to ask any question. If you found that my reply is helpful, you can mark it as an answer to simplify the future search of other people. – StepUp Dec 08 '18 at 11:42

Check equality to a set of values in an array with a specific value and return index

1 Answers1