How can you optimize PHP code to make it more concise and efficient when processing form data?

When processing form data in PHP, you can optimize your code by using built-in functions like filter_input() to sanitize and validate input, reducing the need for manual checks and ensuring data integrity. Additionally, you can use ternary operators to streamline conditional statements and avoid unnecessary code repetition.

// Example of optimizing PHP code for processing form data
$username = isset($_POST['username']) ? filter_input(INPUT_POST, 'username', FILTER_SANITIZE_STRING) : '';
$email = isset($_POST['email']) ? filter_input(INPUT_POST, 'email', FILTER_VALIDATE_EMAIL) : '';