How to Add Space Between camelCase Words in Javascript

In this tutorial, you will learn how to add space between camelCase words in javascript. By capitalizing the initial letter of each word and omitting spaces, camelCase is a style of punctuation used to distinguish between the words in a sentence. For a newbie developer, it can be a bit tricky to add space between camelCase words.

There are numerous ways to add space between camelCase words. We are going to use the simplest approach which involves the usage of the regex pattern as well as replace() method. The replace() method searches the string for a particular value or a regex pattern and it returns a new string with the replaced values.

In the following example, we have one global variable that holds a string. Upon click of a button, we will add space between camelCase words 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, and h1). The div element is just a wrapper for the rest of the elements.
  • The innerText for the button element is “Add” and for the h1 element, it is “Result”.
  • We have done some basic styling using CSS and added the link to our style.css stylesheet inside the head element.
  • We have also included our javascript file script.js with a script 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 and h1 element using the document.querySelector() method and stored them in btnAdd and output variables respectively.
  • We have a global variable myString which holds a string as its value.
  • We are displaying myString in the h1 element using innerText property.
  • We have attached a click event listener to the button element.
  • In the event handler function, we are using replace() method with a regex a pattern. The $1, $2 and $3 indicates the results of the corresponding matching parentheses in the regular expression pattern. The $& is a backreference to the whole match. We are storing the final string in the result variable.
  • We are displaying the result in the h1 element using the innerText property.
let btnAdd = document.querySelector("button");
let output = document.querySelector("h1");

let myString = `fileUploadingProcess`;
output.innerText =  myString;
 
btnAdd.addEventListener("click", () => {  
  let result = myString.replace(/([a-zA-Z])([A-Z])([a-z])/g, '$1 $2$3');
  output.innerText = result;
});