html form validation
<script language = "JavaScript">
function validate() {
var username = document.getElementById("username").value;
var password = document.getElementById("password").value;
if (username == null || username == "") {
alert("Please enter the username.");
return false;
}
if (password == null || password == "") {
alert("Please enter the password.");
return false;
}
alert('Login successful');
}
</script>
<!DOCTYPE html>
<html>
<head>
<script>
function validateForm() {
var x = document.forms["myForm"]["fname"].value;
if (x == "") {
alert("Name must be filled out");
return false;
}
}
</script>
</head>
<body>
<form name="myForm" action="/action_page.php" onsubmit="return validateForm()" method="post">
Name: <input type="text" name="fname">
<input type="submit" value="Submit">
</form>
</body>
</html>
<form action="">
<label for="name">Username</label>
<input id="name" type="text" required />
<label for="Email">Email</label>
<!-- The required attribute will prompt the user to make sure -->
<!-- the fields are not empty, and that the email is formatted correctly -->
<!-- if you want to use custom validation you should use regex in JavaScript -->
<input id="Email" type="text" required />
</form>
