index.php
<?php
$con = mysqli_connect("localhost", "root", "", "check-username");
$sql = "SELECT * FROM emp_details";
$result = mysqli_query($con, $sql);
?>
<!DOCTYPE html>
<html lang="en">
<head>
<title>Check username availability using ajax php mysqli</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<!-- Latest compiled and minified CSS -->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css">
<!-- jQuery library -->
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script>
<!-- Popper JS -->
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.16.0/umd/popper.min.js"></script>
<!-- Latest compiled JavaScript -->
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.5.2/js/bootstrap.min.js"></script>
<link rel="stylesheet" href="css/style.css">
</head>
<body>
<div class="container mt-5">
<div class="row">
<div class="col-md-5 center">
<form action="" method="post">
<label for="username"><b>User Name</b></label>
<input type="text" name="username" placeholder="Username" id="username" required />
<p id="availability"></p>
<button type="submit" name="register" class="btn registerbtn shadow-none" id="register" disabled>Register</button>
<p id="msg"></p>
</form>
</div>
</div>
</div>
</div>
</body>
</html>
<script>
$("#register").click(function(e) {
e.preventDefault();
var username = document.getElementById("username").value;
if (username == "") {
$("#msg").html("Please Enter Username");
$("#msg").show();
$("#msg").focus();
$("#msg").delay(4000).fadeOut("slow");
return false;
}
});
$(document).ready(function() {
$('#username').keyup(function() {
var username = $(this).val();
if (username == "") {
$('#availability').html('');
} else {
$.ajax({
url: 'check_user.php',
method: "POST",
data: {
user_name: username
},
success: function(data) {
if (data != '0') {
$('#availability').html('<span class="text-danger">
Username not available</span>');
$('#register').attr("disabled", true);
} else {
$('#availability').html('<span class="text-success">
Username Available</span>');
$('#register').attr("disabled", false);
}
}
})
}
});
});
</script>
check-user.php
<?php
$connect = mysqli_connect("localhost", "root", "", "check-username");
if(isset($_POST["user_name"]))
{
$username = mysqli_real_escape_string($connect, $_POST["user_name"]);
$query = "SELECT * FROM users WHERE user_name = '".$username."'";
$result = mysqli_query($connect, $query);
echo mysqli_num_rows($result);
}
?>
style.css
.center {
margin: 0 auto;
}
input[type=text],
input[type=password] {
width: 100%;
padding: 15px;
margin: 5px 0 22px 0;
display: inline-block;
border: none;
background: #f1f1f1;
}
input[type=text]:focus,
input[type=password]:focus {
background-color: #ddd;
outline: none;
}
.registerbtn {
background-color: #4CAF50;
color: white;
padding: 16px 20px;
margin: 2px 0;
border: none;
cursor: pointer;
width: 100%;
opacity: 0.9;
}
.registerbtn:hover {
opacity: 1;
}
.signin {
background-color: #f1f1f1;
text-align: center;
}
