think\Session::get PHP Method

    public static function get($name = '', $prefix = null)
    {
        empty(self::$init) && self::boot();
        $prefix = !is_null($prefix) ? $prefix : self::$prefix;
        if ('' == $name) {
            // 获取全部的session
            $value = $prefix ? !empty($_SESSION[$prefix]) ? $_SESSION[$prefix] : [] : $_SESSION;
        } elseif ($prefix) {
            // 获取session
            if (strpos($name, '.')) {
                list($name1, $name2) = explode('.', $name);
                $value = isset($_SESSION[$prefix][$name1][$name2]) ? $_SESSION[$prefix][$name1][$name2] : null;
            } else {
                $value = isset($_SESSION[$prefix][$name]) ? $_SESSION[$prefix][$name] : null;
            }
        } else {
            if (strpos($name, '.')) {
                list($name1, $name2) = explode('.', $name);
                $value = isset($_SESSION[$name1][$name2]) ? $_SESSION[$name1][$name2] : null;
            } else {
                $value = isset($_SESSION[$name]) ? $_SESSION[$name] : null;
            }
        }
        return $value;
    }

 /**
  * 跳转到上次记住的url
  */
 public function restore()
 {
     if (Session::has('redirect_url')) {
         $this->data = Session::get('redirect_url');
         Session::delete('redirect_url');
     }
 }