PHP Programmers Summary of 13 Good Habits of Foreign PHP Programmers

These are the 13 good PHP coding habits listed in this article. If you have better suggestions, please post them in the comments at the end of this article. I like to seek knowledge
1. When using select to query information from the same database, Use a join statement to get all the information you need neatly at once instead of writing multiple mysql_query/while/mysql_fetch_array statements.
2. If you call a database connection in multiple files, create a connection.php file to save your connection variables, and include this file where needed.
3. For small projects, write all your functions in a file. If it is a large project, write them in objects, and then include this file where needed.
4. If your include files are out of control, you can create an include file that contains all the .inc files, and then include this include file where you need it.
5. Write documentation for your code. You will need it when you look at the code 3 months later.
6. Code formatting, nothing is more important than readability.
7. Separate the logic and presentation layers.
8. When writing classes, make sure you know when is the best time to couple and when is the best time to extend.
9. Interface is your friend.
10. When projects get bigger, breaking your code into models, views, and controllers is a super duper.
11. Never output POST and GET data without stripping off the HTML tags.
12. Never trust input from the user, even if she is your mother.
13. Never repeat class names, remember, never!

The above is a summary of 13 good habits of PHP programmers and foreign PHP programmers, including content about PHP programmers. I hope it will be helpful to friends who are interested in PHP tutorials.