<h2>Input field validation via JavaScript</h2>
<p>Press Submit button without entering any text.</p>
<form name="myForm" action= "/action_page.php" onsubmit="return validateForm()" method="post" required>
Name: <input type="text" name="fname">
<input type="submit" value="Submit">
</form>
function validateForm() {
var x = document.forms["myForm"]["fname"].value;
if (x == "" || x == null) {
alert("Name must be filled out");
return false;
}
}
This Pen doesn't use any external CSS resources.
This Pen doesn't use any external JavaScript resources.