The Roman Numeral Converter is a handy JavaScript tool that allows you to effortlessly convert decimal numbers into Roman numerals. It works by utilizing two arrays: one containing decimal values and the other with corresponding Roman numerals.
The main functionality is encapsulated in the convertToRoman method, which takes a numeric input and returns its Roman numeral representation. This code is helpful for quickly converting numbers to Roman numerals, making it a handy tool for various applications.
How to Convert Numbers to Roman Numerals Using Javascript
1. First of all, load the Google Fonts by adding the following CDN link into the head tag of your webpage’s <head> tag. (Optional)
<link rel='stylesheet' href='https://fonts.googleapis.com/css?family=Muli&display=swap'>
2. Within the HTML file, include an input field for entering decimal numbers, a button to trigger the conversion, and an area to display the Roman numeral result. For example:
<div id="container">
<div class="panel">
<h1>Roman Numeral Converter</h1>
<h4>
<span>Convert the number into a</span> <span>roman numeral</span>
</h4>
<input id="convert" type="text" placeholder="Type any number..." />
<button
onclick="convertToRoman(document.getElementById('convert').value)"
>
Convert
</button>
<div class="result-container">
<span id="result"></span>
<button class="btn" id="clipboard">
<i class="far fa-clipboard"></i>
</button>
</div>
<small>
Click the "Convert" button for the result. <br />
You can also copy Roman Numerals by clicking the icon on the right
side of the result.
</small>
</div>
</div>
3. Now, style the basic interface for the converter using the following CSS styles:
* {
margin: 0;
padding: 0;
box-sizing: border-box;
}
body {
font-family: "Muli", sans-serif;
color: #fff;
height: 100vh;
text-align: center;
}
#container {
/*Photo by Cristina Gottardi on Unsplash - https://unsplash.com/photos/I1Lv2yX67GI*/
background-image: linear-gradient(rgba(0, 0, 0, 0.3), rgba(0, 0, 0, 0.3)),
url("https://images.unsplash.com/photo-1525874684015-58379d421a52?ixlib=rb-1.2.1&ixid=eyJhcHBfaWQiOjEyMDd9&auto=format&fit=crop&w=1650&q=80");
width: 100vw;
height: 100vh;
background-size: cover;
background-position: bottom center;
display: flex;
align-items: center;
justify-content: center;
}
.panel {
background-image: linear-gradient(rgba(0, 0, 0, 0.7), rgba(0, 0, 0, 0.7));
border-radius: 15px;
padding: 30px;
margin: 15px;
}
.panel h4,
h1 {
margin-bottom: 20px;
letter-spacing: 0.5px;
}
.panel h4 span:first-of-type {
opacity: 0.5;
}
.panel span:nth-of-type(2) {
color: #dd87ff;
}
.panel input,
.panel button {
border: none;
border-radius: 3px;
display: block;
font-size: 16px;
padding: 8px 10px;
margin: 15px 0;
width: 100%;
}
.panel button {
background-image: linear-gradient(to bottom right, #c564eb, #c85ff1);
border: 1px solid rgba(255, 255, 255, 0.3);
color: #fff;
cursor: pointer;
}
.panel small {
font-size: 0.75em;
line-height: 10px;
opacity: 0.5;
letter-spacing: 1px;
}
.result-container {
background-color: rgba(0, 0, 0, 0.4);
display: flex;
justify-content: flex-start;
align-items: center;
position: relative;
font-size: 18px;
letter-spacing: 1px;
padding: 12px 10px;
height: 50px;
width: 100%;
margin: 15px 0;
}
.result-container #result {
word-wrap: break-word;
max-width: calc(100% - 40px);
}
.result-container .btn {
font-size: 20px;
position: absolute;
top: 5px;
right: 5px;
height: 40px;
width: 40px;
margin: 0;
}
.btn {
border: none;
color: #fff;
cursor: pointer;
font-size: 16px;
padding: 8px 12px;
}
4. Load the Font Awesome Icons Kit by adding the following CDN link just before closing the <body> element:
<script src='https://kit.fontawesome.com/7a230f0a67.js'></script>
5. Finally, include the following JavaScript code into your HTML file, either by linking an external file or placing it within <script> tags.
function convertToRoman(num) {
let decimalValue = [1000, 900, 500, 400, 100, 90, 50, 40, 10, 9, 5, 4, 1];
let romanNumeral = [
"M",
"CM",
"D",
"CD",
"C",
"XC",
"L",
"XL",
"X",
"IX",
"V",
"IV",
"I"
];
let romanized = "";
for (let index = 0; index < decimalValue.length; index++) {
while (decimalValue[index] <= num) {
romanized += romanNumeral[index];
num -= decimalValue[index];
}
}
if (typeof num === "number") {
return (document.getElementById("result").innerHTML = romanized);
}
return (document.getElementById("result").innerHTML =
"Your input is not valid!");
}
document.getElementById("clipboard").addEventListener("click", copyToClipboard);
function copyToClipboard() {
let copyText = document.getElementById("result");
let textArea = document.createElement("textarea");
const emptyResultField = result.innerText;
if (!emptyResultField) {
return;
}
textArea.value = copyText.textContent;
document.body.appendChild(textArea);
textArea.select();
document.execCommand("Copy");
textArea.remove();
alert("Roman numerals copied to clipboard!");
}
That’s all! hopefully, you have successfully created a Roman Numeral Converter using JavaScript. If you have any questions or suggestions, feel free to comment below.
Similar Code Snippets:
Caesar Cipher Encrypt and Decrypt in JavaScript- US Phone Number Validation in JavaScript
- SMS OTP Input Animation in HTML CSS
I code and create web elements for amazing people around the world. I like work with new people. New people new Experiences.
I truly enjoy what I’m doing, which makes me more passionate about web development and coding. I am always ready to do challenging tasks whether it is about creating a custom CMS from scratch or customizing an existing system.