Alternative message_PHP tutorial

How to write a message board for a free personal homepage space that supports PHP but does not support users' MySQL? In fact, there is another very simple way to write a message board, which is to operate text files. I made one on the free hip-hop homepage. You can leave a message!
Write two PHP files (note.php and result.php) and add a text file (note.txt) to save the message record.

Okay, let’s look at the example first: (note.php)