How to protect against xss in php?

@cortez.connelly 

Cross-site scripting (XSS) attacks are a type of injection attack in which an attacker injects malicious code into a website. To protect against XSS attacks in PHP, you can follow these best practices:

1. Validate user input: Use built-in functions such as filter_var() and htmlspecialchars() to validate and sanitize user input.
2. Use prepared statements with parameterized queries: Prepared statements can help protect against SQL injection attacks by using placeholders for user input.
3. Set the HTTP header Content-Security-Policy: This header allows you to specify which domains are allowed to load resources on your website, helping to prevent XSS attacks.
4. Use the escape function: When outputting user-provided data to an HTML page, use the escape function to encode special characters as HTML entities. This will prevent the browser from interpreting the input as code.
5. Use the htmlentities function: This function converts all applicable characters to HTML entities, which can help prevent XSS attacks by encoding any HTML or JavaScript that may be included in user input.

By following these best practices, you can help protect your website and your users against XSS attacks.