<html>
<body>
<form method="post" action="<?php echo $_SERVER['PHP_SELF'];?>">
Name: <input type = "text" name = "name" />
<input type = "submit" />
</form>
<?php
if ($_SERVER["REQUEST_METHOD"] == "POST") {
$name = $_POST['name'];
if (empty($name)) {
echo "Name is empty";
} else {
echo "Welcome ".$name;
}
}
?>
</body>
</html>
Output: