PHP Best Practices
Writing good PHP code goes beyond making it work — it means writing code that is secure, readable, and maintainable over time. This includes validating input, handling errors properly, and following consistent naming conventions.
Following established coding standards (like PSR standards) and keeping functions small and focused makes your PHP projects easier to understand, test, and extend as they grow.
// Good habits, not new syntaxSecurity habits
Always validate and sanitize user input, use prepared statements for database queries, escape output with htmlspecialchars(), and never trust data from the client.
Code quality habits
Use meaningful variable and function names, keep functions focused on a single task, add comments explaining why, and follow a consistent coding style like PSR-12.
<?php
function calculateTotal(array $prices): float {
return array_sum($prices);
}
echo calculateTotal([9.99, 4.99, 2.50]);
?>17.48A clearly named function with a type-hinted parameter and return type is easy to understand and reuse.
<?php
$comment = $_POST["comment"] ?? "";
echo htmlspecialchars($comment);
?>(safely escaped output)Using the null coalescing operator (??) avoids undefined index warnings, and htmlspecialchars() prevents XSS.
Key points
- Always validate and sanitize input, and escape output.
- Use prepared statements for all database queries involving user input.
- Give functions and variables clear, descriptive names.
- Follow consistent coding standards such as PSR-12 across a project.