How to concatenate two strings without duplicates in JavaScript [duplicate]

Question

I have two strings as below:

var str1 = "5YRS,AC,ALAR";
var str2 = "MON,5YRS,TRAU";

I want to merge these two strings into one string and to remove duplicates in this. I tried the below method:

var main_str = str1.concat(str2) //result: "5YRS,AC,ALARMON,5YRS,TRAU"

Result which i got is getting merged at on end and if i push any string dynamically it is not showing the desired result. Is there any new ES6 implementation to get a method which checks both null check and return unique string values.

Answer 1

You could join the two strings with an array and then split the values for getting unique results from a Set.

var str1 = "5YRS,AC,ALAR",
    str2 = "MON,5YRS,TRAU",
    joined = Array.from(new Set([str1, str2].join(',').split(','))).join(',');

console.log(joined);

Answer 2

You can use Set to avoid duplicates:

var str1 = "5YRS,AC,ALAR";
var str2 = "MON,5YRS,TRAU";
var res = [...new Set([...str1.split(','), ...str2.split(',')])].join(',');
console.log(res);

OR:

var str1 = "5YRS,AC,ALAR";
var str2 = "MON,5YRS,TRAU";
var res = [...new Set(str1.split(',').concat(str2.split(',')))].join(',');
console.log(res);