think\Session::set PHP Method

    public static function set($name, $value = '', $prefix = null)
    {
        empty(self::$init) && self::boot();
        $prefix = !is_null($prefix) ? $prefix : self::$prefix;
        if (strpos($name, '.')) {
            // 二维数组赋值
            list($name1, $name2) = explode('.', $name);
            if ($prefix) {
                $_SESSION[$prefix][$name1][$name2] = $value;
            } else {
                $_SESSION[$name1][$name2] = $value;
            }
        } elseif ($prefix) {
            $_SESSION[$prefix][$name] = $value;
        } else {
            $_SESSION[$name] = $value;
        }
    }

 public function set_id($id)
 {
     $arr['msg'] = "this id is " . $id;
     $arr['id'] = $id;
     $arr["d"] = \org\Test::a();
     \think\Session::set("uid", $id);
     return $arr;
 }