In this tutorial, we will learn how to develop a Form Validator Project with plain JavaScript, HTML, and CSS.
Form Validator (Intro Project)
Simple client-side form validation. Check required, length, email, and password match.
Project Specifications
- Create form UI
- Show error messages under specific inputs
- checkRequired() to accept array of inputs
- checkLength() to check min and max length
- checkEmail() to validate email with regex
- checkPasswordsMatch() to match confirm password
JavaScript Breakout Game Development
Create a folder called form-validator as the project workspace and we will create all the project files inside this folder.
1. index.html
Let's create index.html and add the following code to it:
<!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>Form Validator</title>
</head>
<body>
<div class="container">
<form id="form" class="form">
<h2>Register With Us</h2>
<div class="form-control">
<label for="username">Username</label>
<input type="text" id="username" placeholder="Enter username" />
<small>Error message</small>
</div>
<div class="form-control">
<label for="email">Email</label>
<input type="text" id="email" placeholder="Enter email" />
<small>Error message</small>
</div>
<div class="form-control">
<label for="password">Password</label>
<input type="password" id="password" placeholder="Enter password" />
<small>Error message</small>
</div>
<div class="form-control">
<label for="password2">Confirm Password</label>
<input
type="password"
id="password2"
placeholder="Enter password again"
/>
<small>Error message</small>
</div>
<button type="submit">Submit</button>
</form>
</div>
<script src="script.js"></script>
</body>
</html>
2. script.js
Let's create a JavaScript file named script.js and add the following JavaScript code to it:
const form = document.getElementById('form');
const username = document.getElementById('username');
const email = document.getElementById('email');
const password = document.getElementById('password');
const password2 = document.getElementById('password2');
// Show input error message
function showError(input, message) {
const formControl = input.parentElement;
formControl.className = 'form-control error';
const small = formControl.querySelector('small');
small.innerText = message;
}
// Show success outline
function showSuccess(input) {
const formControl = input.parentElement;
formControl.className = 'form-control success';
}
// Check email is valid
function checkEmail(input) {
const re = /^(([^<>()\[\]\\.,;:\s@"]+(\.[^<>()\[\]\\.,;:\s@"]+)*)|(".+"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/;
if (re.test(input.value.trim())) {
showSuccess(input);
} else {
showError(input, 'Email is not valid');
}
}
// Check required fields
function checkRequired(inputArr) {
let isRequired = false;
inputArr.forEach(function(input) {
if (input.value.trim() === '') {
showError(input, `${getFieldName(input)} is required`);
isRequired = true;
} else {
showSuccess(input);
}
});
return isRequired;
}
// Check input length
function checkLength(input, min, max) {
if (input.value.length < min) {
showError(
input,
`${getFieldName(input)} must be at least ${min} characters`
);
} else if (input.value.length > max) {
showError(
input,
`${getFieldName(input)} must be less than ${max} characters`
);
} else {
showSuccess(input);
}
}
// Check passwords match
function checkPasswordsMatch(input1, input2) {
if (input1.value !== input2.value) {
showError(input2, 'Passwords do not match');
}
}
// Get fieldname
function getFieldName(input) {
return input.id.charAt(0).toUpperCase() + input.id.slice(1);
}
// Event listeners
form.addEventListener('submit', function(e) {
e.preventDefault();
if(!checkRequired([username, email, password, password2])){
checkLength(username, 3, 15);
checkLength(password, 6, 25);
checkEmail(email);
checkPasswordsMatch(password, password2);
}
});
3. style.css
Let's create a CSS file named style.css and add the following CSS code to it:
@import url('https://fonts.googleapis.com/css?family=Open+Sans&display=swap');
:root {
--success-color: #2ecc71;
--error-color: #e74c3c;
}
* {
box-sizing: border-box;
}
body {
background-color: #f9fafb;
font-family: 'Open Sans', sans-serif;
display: flex;
align-items: center;
justify-content: center;
min-height: 100vh;
margin: 0;
}
.container {
background-color: #fff;
border-radius: 5px;
box-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
width: 400px;
}
h2 {
text-align: center;
margin: 0 0 20px;
}
.form {
padding: 30px 40px;
}
.form-control {
margin-bottom: 10px;
padding-bottom: 20px;
position: relative;
}
.form-control label {
color: #777;
display: block;
margin-bottom: 5px;
}
.form-control input {
border: 2px solid #f0f0f0;
border-radius: 4px;
display: block;
width: 100%;
padding: 10px;
font-size: 14px;
}
.form-control input:focus {
outline: 0;
border-color: #777;
}
.form-control.success input {
border-color: var(--success-color);
}
.form-control.error input {
border-color: var(--error-color);
}
.form-control small {
color: var(--error-color);
position: absolute;
bottom: 0;
left: 0;
visibility: hidden;
}
.form-control.error small {
visibility: visible;
}
.form button {
cursor: pointer;
background-color: #3498db;
border: 2px solid #3498db;
border-radius: 4px;
color: #fff;
display: block;
font-size: 16px;
padding: 10px;
margin-top: 20px;
width: 100%;
}
Open index.html in Browser
Let's open the index.html file in the browser and you will be able to see the following screen:
More Free JavaScript Projects with Source Code
- JavaScript Tic Tac Toe Game
- JavaScript Project - Modal Box
- JavaScript Project - Modal Box
- JavaScript Project - Password Generator
- JavaScript Project - Weather App
- JavaScript Project - Todo App
- JavaScript Project - Notes App
- JavaScript Project - Movie App
- JavaScript Project - Drawing App
- JavaScript Project - Countdown Timer
- Breakout Game with JavaScript, HTML, and CSS
- Exchange Rate Project with JavaScript, HTML, and CSS
- Expense Tracker Project with JavaScript, HTML, and CSS
- Form Validator with JavaScript, HTML, and CSS
- LyricsSearch App with JavaScript, HTML and CSS
- Movie Seat Booking Project with JavaScript, HTML, and CSS
Comments
Post a Comment