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