How to Add a Variable to a String in Javascript
In this tutorial, you will learn how to add a variable to a string in javascript. A string is any collection of letters, numbers, punctuation, special characters, etc. The numbers range from 0 to 9, but in order to make greater numbers, we must add up multiple smaller ones. For a newbie developer, it can be a bit tricky to add a variable to a string.
There are numerous ways to add a variable to a string. But for the sake of simplicity, we will make use of template string which helps in creating a dynamic string by using variables in it.
In the following example, we have two global variables, one is holding a number and another one a string. Upon click of a button, we will add a variable to a string 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
name
andage
where one variable holds a string and another one a number. - We have attached a
click
event listener to thebutton
element. - In the event handler function, we are creating a string dynamically where we we are using global variables
name
andage
. - 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 name = "Jake"; let age = 31; btnAdd.addEventListener("click", () => { let result = `${name} is ${age} years old`; output.innerText = result; });