JavaScript Arrays - Remove duplicates and just return just one

Question

If I have an array (category) that have multiple of the same values (retail for example)

How do I remove duplicates and just return just one (Retail, Technology, Auto etc)

So it just leaves data like this:

Before:

category: “Retail, Retail, Retail, Technology”,

After:

category: “Retail, Technology”

I have a code example here:

https://codesandbox.io/s/late-cdn-2stdj

Update:

See when I do it with const of categories it works:

https://codesandbox.io/s/inspiring-sky-zx4mo

but when I try and do it with a .map to access the array it doesn't that is where I am at:

https://codesandbox.io/s/late-cdn-2stdj

I might have tried searching for this first. – Dave Newton Mar 10 '20 at 07:12 — Dave Newton, Mar 10 '20 at 07:12

Chau Giang · Accepted Answer · 2020-03-11T01:34:40.597

1

Use Set:

const categories = "Retail, Retail, Retail, Technology";

const listCategories = [...new Set(categories.split(/,\s*/))];

Or alternative:
const listCategories = [...new Set(categories.match(/[A-z]+/g))];


const result = listCategories.join(", ");
console.log({result})

edited Mar 11 '20 at 01:34

answered Mar 10 '20 at 07:11

Chau Giang

1,414
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@Tired_Man you are most welcome! – Chau Giang Mar 10 '20 at 08:07

JavaScript Arrays - Remove duplicates and just return just one

1 Answers1