How can PHP developers ensure the security of values passed through URLs in dynamic webpages?

To ensure the security of values passed through URLs in dynamic webpages, PHP developers can sanitize and validate the input data to prevent SQL injection, cross-site scripting (XSS), and other security vulnerabilities. One way to achieve this is by using PHP functions like filter_input() or htmlentities() to sanitize user input before using it in SQL queries or displaying it on the webpage.

// Example of sanitizing input data from a URL parameter
$input_value = filter_input(INPUT_GET, 'parameter_name', FILTER_SANITIZE_STRING);

// Example of displaying sanitized input on the webpage
echo htmlentities($input_value);