In what scenarios should data escaping be implemented in PHP, regardless of successful validation checks?

Data escaping should be implemented in PHP whenever user input is being displayed on a webpage, even if successful validation checks have been performed. This is because escaping the data helps prevent cross-site scripting (XSS) attacks by converting special characters into their HTML entities. By escaping the data, you ensure that any potentially malicious code entered by users is rendered harmless when displayed on the webpage. 

// Example of implementing data escaping in PHP
$user_input = "<script>alert('XSS attack!');</script>";

// Escaping the user input before displaying it on the webpage
$escaped_input = htmlspecialchars($user_input, ENT_QUOTES, 'UTF-8');

// Displaying the escaped input on the webpage
echo $escaped_input;

Keywords

SQL injection cross-site scripting (XSS) htmlentities htmlspecialchars input validation

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