How to Add a Character to the Beginning of a String in Javascript
In this tutorial, you will learn how to add a character to the beginning of a string in javascript. A string consists of numerous characters. Characters at the beginning of a string add some uniqueness to it and make it look more meaningful. For a newbie developer, it can be a bit tricky to add a character to the beginning of a string.
There are numerous ways to add a character to the beginning of a string. But for the sake of simplicity, we will make use of addition operator (+
) which helps in concatenating two individual strings.
In the following example, we have one global variable that holds a string. Upon click of a button, we will add a character to the beginning of the 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 a global variable
myString
which holds a string as its value. - We are displaying
myString
in theh1
element usinginnerText
property. - We have attached a
click
event listener to thebutton
element. - In the event handler function, we have character
"K"
stored in themyChar
variable. We are adding it to themyString
using addition operator (+
) and storing the final string in theresult
variable. - We are displaying the
result
in theh1
element using theinnerText
property.
let btnAdd = document.querySelector("button"); let output = document.querySelector("h1"); let myString = `eep going`; output.innerText = myString; btnAdd.addEventListener("click", () => { let myChar = "K" let result = myChar + myString; output.innerText = result; });