public function getUser($username,$password) {
      $sql="SELECT * from reg_users where user_name=? AND password=?";
      mysqli_prepare($con,$sql);
      mysqli_bind_param($sql,"ss",$username,$password);
       mysqli_stmt_execute($sql);
      $row_cnt = mysqli_num_rows($sql);
      $result=array();
while($row = mysqli_fetch_array($res)){
      array_push($result,array("count"=>$row_cnt);
}
      echo json_encode(array("result"=>$result));

    }