登入登出

最近看到這種寫法還滿不錯的
以往寫網頁時並不會想到這種用法

echo login_program();

function login_program(){
  $ex_target = ex_target("login.php","登入");
    if (session_is_registered("login_session")){
      $ex_target = ex_target("logout.php","登出");
    }
  return $ex_target;
}

function ex_target($ex_app,$ex_text){
  return "$ex_text";
}