Popup boxes in JavaScript
The pop-up boxes are small GUI frames used to make the user aware, warn or ask something. JavaScript provides three types of popup boxes the Alert box, the Confirm box, and the Prompt box.
The alert box
The alert box is mostly used to provide information(alert message) about something to the user. When we want that user is ensured about some information we can use an Alert box. There is only one option(OK) available with an alert box. The user can click ok and move ahead.
The syntax for the alert box is
window.alert("message");
however, using a window object is not necessary we can directly use alert() method without window object.
<script>
window.alert("are
you sure to move ahead???");
</script>
The confirm box
The confirm box is very much similar to the Alert box, but a confirm box is also able to display a cancel button along with the ok button(two options). The ok button will return true and the cancel button will return false upon the click.
Confirm box is mostly used if we want the user to ensure about accepting something. The user may accept or cancel.
The syntax for confirm box is
window.confirm("message");
<script>
window.confirm("are you sure to move ahead???");
</script>
The prompt box
The prompt box has two options available for the user, like the confirm box ok and cancel, but the user can also provide some input in an input text field in a prompt box. In other words, we can ask for some input from the user using the prompt box.
The syntax for the prompt box is
window.prompt("Enter your name?","default");
<script>
val=window.prompt("What is your name???","Johny");
</script>
Prompt Box Example
<html>
<head>
<script>
function
testPrompt()
{
name=window.prompt('Enter your name?','');
if(name!='')
{
document.getElementById('demo').innerHTML='Welcome
'+name;
}
else
{
document.getElementById('demo').innerHTML='Unknown
user';
}
}
</script>
</head>
<body>
<button onclick="testPrompt()">Click me</button>
<div id='demo'></div>
</body>
</html>
