How can PHP developers ensure proper data validation and sanitization when passing variables between pages?

To ensure proper data validation and sanitization when passing variables between pages in PHP, developers should use functions like filter_input() for input validation and filter_var() for data sanitization. These functions help prevent security vulnerabilities such as SQL injection and cross-site scripting attacks by validating and sanitizing user input before using it in the application. 

// Validate and sanitize input data
$username = filter_input(INPUT_POST, 'username', FILTER_SANITIZE_STRING);
$email = filter_input(INPUT_POST, 'email', FILTER_VALIDATE_EMAIL);

// Use the sanitized data in the application
echo "Username: " . $username;
echo "Email: " . $email;

Keywords

PHP data validation sanitization variables security

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