How to add HTML oninvalid Attribute

Input Example. If you click submit, without filling out the text field, an alert message will occur. Note: The oninvalid event is not supported in Safari.

index.html

Example: HTML

<!DOCTYPE html>
<html>
<body>

<form action="/action_page.php" method="get">
  Name: <input type="text" oninvalid="alert('You must fill out the form!');" name="fname" required>
  <input type="submit" value="Submit">
</form>

<p>If you click submit, without filling out the text field, an alert message will occur.</p>

<p><strong>Note:</strong> The oninvalid event is not supported in Safari.</p>

</body>
</html>

Output should be:

Type:	html
Category:	Web Tutorial
Sub Category:	HTML Attribute
Uploaded by:	Admin