August 11, 2022
How to Join Two Values in Javascript
In this tutorial, you will learn how to join two values in javascript. One or more strings may need to be added to a single word or string in order to give it meaning in some cases. For a newbie developer, it can be a bit tricky to join two values.
There are numerous ways to join two values. But for the sake of simplicity, we will make use of addition operator (+
) which helps in concatenating two or more strings.
In the following example, we have two global variables that are holding a string value. Upon click of a button, we will join two values and display the result on the screen. Please have a look over the code example and the steps given below.
HTML & CSS
- We have 3 elements in the HTML file (
div
,button
, andh1
). Thediv
element is just a wrapper for the rest of the elements. - The
innerText
for thebutton
element is“Add”
and for theh1
element, it is“Result”
. - We have done some basic styling using CSS and added the link to our
style.css
stylesheet inside thehead
element. - We have also included our javascript file
script.js
with ascript
tag at the bottom.
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <meta http-equiv="X-UA-Compatible" content="ie=edge"> <link rel="stylesheet" href="style.css"> <title>Document</title> </head> <body> <div class="container"> <button>Add</button> <h1>Result</h1> </div> <script src="script.js"></script> </body> </html>
.container { text-align: center; } button { margin-top: 10px; padding: 10px 20px; }
Javascript
- We have selected the
button
element andh1
element using thedocument.querySelector()
method and stored them inbtnAdd
andoutput
variables respectively. - We have two global variables
firstName
andlastName
. They both hold a string as a value. - We have attached a
click
event listener to thebutton
element. - In the event handler function, we are concatenating
firstName
andlastName
variables using addition operator (+
) . - We are storing the final string in the
result
variable. - We are displaying the
result
in theh1
element using theinnerText
property.
let btnAdd = document.querySelector("button"); let output = document.querySelector("h1"); let firstName = `Kate`; let lastName = `Perry`; btnAdd.addEventListener("click", () => { let result = firstName + ' ' + lastName; output.innerText = result; });