What are some common methods to prevent HTML manipulation in PHP?

HTML manipulation in PHP can be prevented by using functions such as htmlentities() or htmlspecialchars() to escape special characters in user input before displaying it on a webpage. This helps to prevent cross-site scripting (XSS) attacks where malicious code can be injected into a webpage. Additionally, validating and sanitizing user input before processing it can also help prevent HTML manipulation.

// Prevent HTML manipulation by escaping special characters in user input
$user_input = "<script>alert('XSS attack');</script>";
$escaped_input = htmlentities($user_input);

echo $escaped_input;