Best Practices in PHP Development

Coding habits that keep your code readable, maintainable, and less bug-prone.

Use a consistent coding style

Consistent formatting makes code easier to read, especially in teams. PHP-FIG publishes PSR standards (PHP Standard Recommendations) as a sensible baseline.

PSR-1 and PSR-12

Basic coding standards for PHP.

<?php
namespace Vendor\Model;

class Foo
{
    public function bar($arg1, &$arg2)
    {
        // Method body
    }
}
?>

Keep code simple and clear

Simple code has fewer bugs and is easier to change later.

Avoid deep nesting

Deeply nested if blocks are hard to follow. Early returns flatten things out.

Before:

<?php
if ($condition1) {
    // Code
    if ($condition2) {
        // More code
        if ($condition3) {
            // Even more code
        }
    }
}
?>

After:

<?php
if (!$condition1) {
    return;
}
// Code
if (!$condition2) {
    return;
}
// More code
if ($condition3) {
    // Even more code
}
?>

Use meaningful names

Variable and function names should say what they hold or do.

Variable naming

// Less clear
$dn = new DateTime();

// More clear
$currentDate = new DateTime();

Function naming

// Less clear
function processData() {
    // ...
}

// More clear
function validateUserInput() {
    // ...
}

Use PHP’s built-in functions

PHP has a large standard library. Check whether something already exists before writing your own.

<?php
$reversedString = strrev("Hello, PHP!");
echo $reversedString;
?>

Sanitise and validate user input

Assume user input is hostile until you have checked it.

Validation

<?php
$email = "test@example.com";
if (!filter_var($email, FILTER_VALIDATE_EMAIL)) {
    echo "Invalid email format";
}
?>

Sanitisation

<?php
$input = "<script>alert('Hack!');</script>";
$safeInput = htmlspecialchars($input);
echo $safeInput;
?>

Use comments wisely

Comments should explain why, not what. If the code needs a comment to explain what it does, consider renaming things instead.

Before:

// Increment x
$x++;

After:

// Compensate for boundary overlap
$x++;

Error handling

Use try-catch for exceptions. Check return values and handle failures explicitly.

<?php
try {
    // Code that may throw an exception
} catch (Exception $e) {
    // Handle exception
}
?>

Database interaction: use prepared statements

Prepared statements prevent SQL injection.

<?php
$stmt = $pdo->prepare("SELECT * FROM users WHERE email = :email");
$stmt->execute(['email' => $email]);
$user = $stmt->fetch();
?>

Version control

Use Git (or similar) to track changes. Essential for team work and rolling back mistakes.

Code reviews

Reviewing each other’s code catches bugs and spreads knowledge. Worth doing even on small teams.

Keep learning

PHP changes. New versions, frameworks, and tools appear regularly. Stay roughly up to date.

These are guidelines, not laws. Apply what fits your project and team, and adjust as you go.