React native for loop getting index [duplicate]

Question

This is probably a super simple question, but I have the following:

let groups = [{}, {}, {}];

for(let g of groups) {
    console.log(g);
}

How do I get the index number of said group? Preferably without doing a count.

I'm not sure about React, but in javascript there is for-in that goes through indices — Stefan Octavian
– Stefan Octavian, Commented Apr 1, 2018 at 17:37

Code-Apprentice · Accepted Answer · 2018-04-01 17:37:58Z

6

Alternatively use forEach():

groups.forEach((element, index) => {
    // do what you want
});

answered Apr 1, 2018 at 17:37

Code-Apprentice

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2 Comments

I get .forEach() is not a function

@bryan Do you have the same definition of groups as in your question?

Axnyff · Accepted Answer · 2018-04-01 17:37:16Z

3

Instead of looping through groups, you could loop through groups.entries() which returns for each element, the index and the value.

Then you can extract those value with destructuring:

let groups = [{}, {}, {}];

for(let [i, g] of groups.entries()) {
    console.log(g);
}

answered Apr 1, 2018 at 17:37

Axnyff

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Matus Dubrava · Accepted Answer · 2018-04-01 17:36:40Z

2

Simply,

let groups = [{}, {}, {}];

for(let g of groups) {
    console.log(groups.indexOf(g));
}

answered Apr 1, 2018 at 17:36

Matus Dubrava

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