Answers for "js how to concat 2 string"

string concatenation in js

var str1 = "Hello ";
var str2 = "world!";
var res = str1.concat(str2);
console.log(res);

js concat string

const str1 = 'Hello';
const str2 = 'World';

console.log(str1.concat(' ', str2));
// expected output: "Hello World"

console.log(str2.concat(', ', str1));
// expected output: "World, Hello"