https://blog.toright.com/posts/4656/%e7%94%a8-php-%e5%af%a6%e7%8f%be-iocdi-%e6%8e%a7%e5%88%b6%e5%8f%8d%e8%bd%89%e8%88%87%e4%be%9d%e8%b3%b4%e6%b3%a8%e5%b0%84-%e8%a8%ad%e8%a8%88%e6%a8%a1%e5%bc%8f