how to add to a string javascript code example

Example 1: string concatenation in js

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

Example 2: string concat javascript

//This method adds two or more strings and returns a new single string.

let str1 = new String( "This is string one" ); 
let str2 = new String( "This is string two" ); 
let str3 = str1.concat(str2.toString());
console.log("str1 + str2 : "+str3)

output:
str1 + str2 : This is string oneThis is string two

Example 3: javascript string concatenation

var totn_string = '';

console.log(totn_string.concat('Tech','On','The','Net'));

//The following will be output to the web browser console log:

TechOnTheNet

Example 4: append string js

var s = "1"
s += "2"

Example 5: javascript add to string

var s = 'hell'
s = s + 'o'

Example 6: string concat in js

let string1 = "Hello"
let string2 = "World"

let finalString = string1 + ", " + string2 + "!" // Hello, World!