How to Change Button Label in Alert Box using JavaScript ?

Last Updated : 16 Apr, 2024

In JavaScript, the alert method is used to display an alert box with a message. By default, the alert box contains an "OK" button. We cannot directly update the default alert box, However, we can customize the button label by creating a custom alert box using HTML, CSS, and JavaScript.

Approach

Create the UI of the web page using different HTML elements, and a stylish alert box using CSS.
Define a hidden HTML div element for the custom alert box. This div will contain the message and the custom button.
Use JavaScript to display the custom alert box when needed. Set the message and the button label dynamically.
Attach an event listener to the custom button to handle its click event.

Example: This example shows how we can implement this approach.

HTML

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" 
          content="width=device-width, initial-scale=1.0">
    <title>Custom Alert Box</title>
    <style>
        h1 {
            color: green;
        }

        body {
            text-align: center;
        }

        .custom-alert {
            display: none;
            position: fixed;
            top: 40%;
            left: 50%;
            transform: translate(-50%, -50%);
            background-color: #f8d7da;
            color: #721c24;
            padding: 10px;
            border: 1px solid #f5c6cb;
            border-radius: 5px;
            text-align: center;
        }
    </style>
</head>

<body>
    <h1>GeeksForGeeks</h1>
    <button onclick="showCustomAlert()">Show Custom Alert</button>

    <div id="customAlert" class="custom-alert">
        <p id="alertMessage"></p>
        <button id="customButton">Close</button>
    </div>

    <script>
        function showCustomAlert() {
            const message = "This is a custom alert box!";
            const buttonText = "Close me";
            const alertBox = document.getElementById('customAlert');
            const alertMessage = document.getElementById('alertMessage');
            const customButton = document.getElementById('customButton');

            // Set the message and button label
            alertMessage.innerText = message;
            customButton.innerText = buttonText;

            // Show the custom alert box
            alertBox.style.display = 'block';

            // Handle button click
            customButton.addEventListener('click', function () {
                alertBox.style.display = 'none'; // Hide the alert box
            });
        }
    </script>
</body>

</html>