if(isset($_POST["login"])){

if(!empty($_POST['username']) && !empty($_POST['password'])) {
$username=htmlspecialchars($_POST['username']);
$password=htmlspecialchars($_POST['password']);
$query =mysqli_query($con, "SELECT * FROM usertbl WHEREusername='".$username."' AND password='".$password."'");
$numrows=mysqli_num_rows($query);
if($numrows!=0)
 {
while($row=mysqli_fetch_assoc($query))
 {
$dbusername=$row['username'];
$dbpassword=$row['password'];
}