Overview: On the road to becoming a PHP master, you should maintain good traditions and habits.
1. Read more manuals and source code
There is nothing more worthy of emphasis than reading the manual - you can learn a lot just by reading the manual, especially many functions about strings and arrays. These functions include many useful functions. If you read the manual carefully, you will often find that in the past project development process, you often "reinvent the wheel", but in fact you only need one core function. Complete the corresponding functions. The manual is your friend. In addition, there are now many open source programs developed using PHP. Why not learn and learn from it? Download a copy of the source code for an open source PHP application and read it carefully. Perhaps the larger projects are more worth reading, although they may have more complex structures and systems, but also have more detailed explanatory documentation.
2. Write modular code
Good PHP code should be modular code. PHP's object-oriented programming capabilities are particularly powerful tools for breaking your application into functions or methods. You should separate as much as possible the front-end HTML/CSS/JavaScript code from the server-side of your application, and you can also follow the MVC (Model-View-Controller) pattern on any PHP framework.
3. Code writing specifications
Good PHP code should have a complete set of coding specifications. Achieving programming standards through naming variables and functions, unified methods for accessing the database and handling errors, and the same code indentation method can make your code more readable.
4. Write portable code
Good PHP code should be portable. You can use PHP's existing features like magic quotes and short tags. Try to understand your needs and then write code to make it self-contained and portable by adapting PHP features.
5. Write secure code
Good PHP code should be secure. PHP5 provides excellent performance and flexibility. But the security issue lies entirely with the developers. For a professional PHP developer, it is crucial to have a deep understanding of major security vulnerabilities, such as: Cross-site scripting (XSS), Cross-site request forgery (CSRF), code injection vulnerabilities, and character encoding vulnerabilities. By using PHP's special features and functions, such as: mysql_real_escape_string, etc., you can write safe code.
6. Code comments
Code comments are an important part of the code. Through code comments, you can know what the variable or function does, which will be very useful in future code maintenance.
7. Use single quotes instead of double quotes
Always use single quotes instead of double quotes for strings to avoid performance degradation caused by PHP searching for variables within the string. It's faster to enclose the string in single quotes instead of double quotes. Because PHP will search for variables in a string surrounded by double quotes, single quotes will not
8. Escape string output
Use ENT_QUOTES as a parameter to pass to the htmlspecialchars function to ensure that single quotes (') are also converted into HTML entities. This is a good habit.
9. Use commas to separate string output
Outputting strings separated by commas (,) through the echo statement has better performance than using the string concatenation operator (.).
10. Check the passed value before outputting
Check the passed value $_GET['query'] before outputting. Using the isset or empty function, you can check whether a variable is null.