NodeJS: How to remove duplicates from Array

Question

I have an array:

Now I want to remove all the duplicates from it. Is there any method in NodeJs which can directly do this.

myArray.filter(function(item , index, arr){ return arr.indexOf(item)=== index}) please ignore my previous comment , read your question incorrectly. — Davet, Jul 17 '15 at 19:34

score 77 · Answer 1 · edited May 23 '17 at 11:54

77

No, there is no built in method in node.js, however there are plenty of ways to do this in javascript. All you have to do is look around, as this has already been answered.

uniqueArray = myArray.filter(function(elem, pos) {
    return myArray.indexOf(elem) == pos;
})

edited May 23 '17 at 11:54

Community

1
1

answered Apr 23 '14 at 08:17

mihai

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Thanks Mihai and Jurka. I was just wondering if there is any built in method to do this. Anyways you guys solved my problem. Best Regards – Yo Yo Saty Singh Apr 23 '14 at 08:37
@YoYoSatySingh It's better to go through `Set` in Node.js now. The browser support is also starting to get there. – Juho Vepsäläinen Dec 21 '17 at 08:18
3

shorter version: `uniques = array.filter((x, i) => i === array.indexOf(x))` – Amin Fazlali Jun 08 '20 at 11:24

Risto Novik · Answer 2 · 2016-06-08T06:50:40.277

No there is no built in method to get from array unique methods, but you could look at library called lodash which has such great methods _.uniq(array).

Also, propose alternative method as the Node.js has now support for Set's. Instead of using 3rd party module use a built-in alternative.

var array = [
    1029,
    1008,
    1040,
    1019,
    1030,
    1009,
    1041,
    1020,
    1031,
    1010,
    1042,
    1021,
    1030,
    1008,
    1045,
    1019,
    1032,
    1009,
    1049,
    1022,
    1031,
    1010,
    1042,
    1021,
];

var uSet = new Set(array);
console.log([...uSet]); // Back to array

exactly - as a oneliner in 2022: `Array.from(new Set(array))` — Ian Carter, Oct 08 '22 at 10:30

NodeJS: How to remove duplicates from Array

2 Answers2